UE, MME, communication control method of UE, and communication control method of MME

ABSTRACT

Included are the steps of: receiving an ATTACH ACCEPT message including at least a Packet Data Network (PDN) address from a core network; and establishing a PDN connection and/or a radio bearer for user data transmission and/or reception, based on the PDN address. Thus, a communication procedure such as an attach procedure suitable for a CIoT terminal is provided.

TECHNICAL FIELD

The present invention relates to a User Equipment (UE) and the like.

This application claims priority based on JP 2015-220104 filed on Nov.10, 2015 in Japan, the contents of which are incorporated herein in itsentirety by reference.

BACKGROUND ART

The 3rd Generation Partnership Project (3GPP), which undertakesactivities for standardizing recent mobile communication systems,discusses System Architecture Enhancement (SAE), which is systemarchitecture of the Long Term Evolution (LTE). 3GPP is in the process ofcreating specifications for the Evolved Packet System (EPS), whichrealizes an all-IP architecture. Note that a core network of LTE iscalled an Evolved Packet Core (EPC).

Furthermore, 3GPP recently discusses a Machine to Machine (M2M)communication technology. Note that the M2M communication may bemachine-machine type communication. 3GPP discusses a Cellular Internetof Things (CIoT), in particular, as a technology for supporting Internetof Things (IoT) in a cellular network of 3GPP.

The IoT includes a mobile phone terminal such as a smartphone, andindicates various IT devices such as a personal computer and a sensordevice. In CIoT, technical problems for connecting such various terminaldevices to a cellular network are extracted, and solutions arestandardized.

For example, CIoT is demanded to optimize communication procedures for aterminal needed to increase the efficiency of power consumption so thata battery can be maintained for several years, to cope withcommunication in an indoor or underground state, and to provideconnectivity to a large amount of terminals produced by inexpensive massproduction. Furthermore, in CIoT, supporting low data rate communicationwith a simple end node is cited as a required condition.

Note that terminals allowed to connect to a 3GPP core network arereferred to CIoT terminals herein.

CITATION LIST Non Patent Literature

-   NPL 1: 3rd Generation Partnership Project; Technical Specification    Group Services and System Aspects; Architecture enhancements for    Cellular Internet of Things; (Release 13)

SUMMARY OF INVENTION Technical Problem

As for CIoT, in order to increase the efficiency of a control signal,including a function unit having multiple functions in the core networkis discussed. Specifically, providing a CIoT Serving Gateway Node(C-SGN) responsible for functions of known MME, SGW, and PGW in the corenetwork is discussed.

3GPP discusses that a CIoT terminal is connected to the core networkthrough an access network of CIoT.

Note that the core network to which the CIoT terminal is connected maybe a known core network accommodating mobile phone terminals such assmartphones, may be a logically-divided core network for accommodatingCIoT terminals, or may be a core network physically different from theknown core network. However, a connection method to these core networksand a procedure for data transmission and/or reception to/from thesecore networks have not been made clear.

The present invention has been made in view of the above describedsituations, and an object is to provide a communication procedure suchas an attach procedure suitable for a CIoT terminal.

Solution to Problem

In order to achieve the above-described object, a User Equipment (UE)according to one aspect of the present invention includes: atransmission and/or reception unit configured to perform an attachprocedure; and a control unit. In the attach procedure, the transmissionand/or reception unit transmits an ATTACH REQUEST message to a MobilityManagement Entity (MME), receives an ATTACH ACCEPT message from the MME,and transmits an ATTACH COMPLETE message to the MME, to notify that, bytransmitting the ATTACH REQUEST message, the UE supports a mode A andthe UE requests the mode A. The ATTACH ACCEPT message includes networkcapability information indicating that the mode A is supported. Thecontrol unit interprets that the mode A is accepted by receiving thenetwork capability information included in the ATTACH ACCEPT message andindicating that the mode A is supported, and is capable of performing atleast first processing after completion of the attach procedure, basedon acceptance of the mode A. The first processing is processing forentering an idle mode to keep a UE context in a case that a message tosuspend an RRC connection is received from a base station device.

An MME according to one aspect of the present invention includes: atransmission and/or reception unit configured to perform an attachprocedure; and a control unit. In the attach procedure, the transmissionand/or reception unit receives an ATTACH REQUEST message from a UserEquipment (UE), transmits an ATTACH ACCEPT message to the UE, andreceives an ATTACH COMPLETE message from the UE, to acquire that, byreceiving the ATTACH REQUEST message, the UE supports a mode A and theUE requests the mode A. The ATTACH ACCEPT message includes networkcapability information indicating that the mode A is supported. Theinformation included in the ATTACH ACCEPT message and indicating thatthe mode A is supported is used by the UE for interpreting that the modeA is accepted. The control unit is capable of performing at least firstprocessing after completion of the attach procedure, based on acceptanceof the mode A. The first processing is processing for entering an idlemode to keep a bearer context for transmitting and/or receiving userdata, in a case that an S1 Application Protocol (S1AP) message isreceived from a base station device.

A communication control method for a User Equipment (UE) according to anaspect of the present invention includes the step of performing anattach procedure. In the attach procedure, the UE transmits an ATTACHREQUEST message to a Mobility Management Entity (MME), receives anATTACH ACCEPT message from the MME, and transmits an attach completionmessage to the MME, to notify that, by transmitting the ATTACH REQUESTmessage, the UE supports a mode A and the UE requests the mode A. TheATTACH ACCEPT message includes network capability information indicatingthat the mode A is supported. The UE interprets that the mode A isaccepted by receiving the network capability information included in theATTACH ACCEPT message and indicating that the mode A is supported, andis capable of performing at least first processing after completion ofthe attach procedure, based on acceptance of the mode A. The firstprocessing is processing for keeping a UE context in a case of enteringan idle mode upon reception of a message to suspend an RRC connectionfrom a base station device.

A communication control method for a Mobility Management Entity (MME)according to one aspect of the present invention includes the step ofperforming an attach procedure. In the attach procedure, the MMEreceives an ATTACH REQUEST message from a UE, transmits an ATTACH ACCEPTmessage to the UE, and receives an ATTACH COMPLETE message from the UE,to acquire that, by receiving of the ATTACH REQUEST message, the UEsupports a mode A and the UE requests the mode A. The ATTACH ACCEPTmessage includes network capability information indicating that the modeA is supported. The information included in the ATTACH ACCEPT messageand indicating that the mode A is supported is used by the UE forinterpreting that the mode A is accepted. At least first processing ispossible to be performed after completion of the attach procedure, basedon acceptance of the mode A. The first processing is processing forentering an idle mode to keep a bearer context for transmitting and/orreceiving user data in a case that an S1 Application Protocol (S1AP)message is received from a base station device.

Advantageous Effects of Invention

According to the present invention, a CIoT terminal can attach and/ordetach a core network which can provide multiple transmission methodsincluding a user data transmission method optimized for the CIoTterminal, to communicate with the core network.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a diagram illustrating an overview of a mobile communicationsystem.

FIG. 2 is a diagram illustrating an example of a configuration of an IPmobile communication network, and the like.

FIG. 3 is a diagram illustrating an example of a configuration of an IPmobile communication network, and the like.

FIG. 4 is a diagram illustrating a device configuration of an eNB.

FIG. 5 is a diagram illustrating a network initiated detach procedure.

FIG. 6 is a diagram illustrating a device configuration of an MME.

FIG. 7 is a diagram illustrating a storage unit of the MME.

FIG. 8 is a diagram illustrating the storage unit of the MME.

FIG. 9 is a diagram illustrating the storage unit of the MME.

FIG. 10 is a diagram illustrating the storage unit of the MME.

FIG. 11 is a diagram illustrating the storage unit of the MME.

FIG. 12 is a diagram illustrating the storage unit of the MME.

FIG. 13 is a diagram illustrating a device configuration of a SGW.

FIG. 14 is a diagram illustrating a storage unit of the SGW.

FIG. 15 is a diagram illustrating the storage unit of the SGW.

FIG. 16 is a diagram illustrating a device configuration of a PGW.

FIG. 17 is a diagram illustrating a storage unit of the PGW.

FIG. 18 is a diagram illustrating the storage unit of the PGW.

FIG. 19 is a diagram illustrating a device configuration of a C-SGN.

FIG. 20 is a diagram illustrating a device configuration of a UE.

FIG. 21 is a diagram illustrating a storage unit of the UE.

FIG. 22 is a diagram illustrating an overview of a communicationprocedure.

FIG. 23 is a diagram illustrating a first attach procedure.

FIG. 24 is a diagram illustrating a second attach procedure.

FIG. 25 is a diagram illustrating a third attach procedure.

FIG. 26 is a diagram illustrating a first transmission and/or receptionprocedure.

FIG. 27 is a diagram illustrating a second transmission and/or receptionprocedure.

FIG. 28 is a diagram illustrating a UE initiated detach procedure.

DESCRIPTION OF EMBODIMENTS

Hereinafter, a preferred embodiment for carrying out the presentinvention will be described with reference to the drawings. Note that asan example, the present embodiment describes an embodiment of a mobilecommunication system to which the present invention is applied.

1. Embodiments

1.1. System Overview

FIG. 1 is a diagram illustrating an overview of a mobile communicationsystem according to the present embodiment. As illustrated in FIG. 1, amobile communication system 1 includes a mobile terminal device UE_A 10,an eNB_A 45, a core network_A 90, and a PDN_A 5.

Here, the UE_A 10 may be any wirelessly connectable terminal device, andmay be a User equipment (UE), a Mobile equipment (ME), or a MobileStation (MS).

The UE_A 10 may be a CIoT terminal. Note that the CIoT terminal is anIoT terminal connectable with a core network A 90, the IoT terminalincludes a mobile phone terminal such as a smartphone, and may bevarious IT devices such as a personal computer and a sensor device.

In other words, in a case that the UE_A 10 is the CIoT terminal, theUE_A 10 may request a connection optimized for the CIoT terminal basedon a policy of the UE_A 10 or a request from the network, or may requestthe known connection. Alternatively, the UE_A 10 may be configured as aterminal device which connects to the core network_A 90 only by acommunication procedure optimized in advance for the CIoT terminal atthe time when the UE_A 10 is shipped.

Here, the core network_A 90 refers to an IP mobile communication networkrun by a Mobile Operator.

For example, the core network_A 90 may be a core network for the mobileoperator that runs and manages the mobile communication system 1, or maybe a core network for a virtual mobile operator such as a Mobile VirtualNetwork Operator (MVNO). Alternatively, the core network_A 90 may be acore network for accommodating the CIoT terminal.

Additionally, the eNB_A 45 is a base station constituting a radio accessnetwork used by the UE_A 10 to connect to the core network_A 90. Inother words, the UE_A 10 connects to the core network_A 90 using theeNB_A 45.

Additionally, the core network_A 90 is connected to the PDN_A 5. ThePDN_A 5 is a packet data service network which provides a communicationservice to the UE_A 10, and may be configured for each service. Acommunication terminal is connected to the PDN, the UE_A 10 can transmitand/or receive user data to/from the communication terminal located inthe PDN_A 5.

Next, an example of a configuration of the core network_A 90 will bedescribed. In the present embodiment, two configuration examples of thecore network_A 90 will be described.

FIG. 2 illustrates a first example of the configuration of the corenetwork_90. The core network_A 90 in FIG. 2(a) includes a HomeSubscriber Server (HSS)_A 50, an Authentication, Authorization,Accounting (AAA)_A 55, a Policy and Charging Rules Function (PCRF)_A 60,a Packet Data Network Gateway (PGW)_A 30, an enhanced Packet DataGateway (ePDG)_A 65, a Serving Gateway (SGW)_A 35, a Mobility ManagementEntity (MME)_A 40, and a Serving GPRS Support Node (SGSN)_A 42.

Furthermore, the core network_A 90 is capable of connecting to multipleradio access networks (an LTE AN_A 80, a WLAN ANb 75, a WLAN ANa 70, aUTRAN_A 20, and a GERAN_A 25).

Such a radio access network may be configured by connecting to multipledifferent access networks, or may be configured by connecting to eitherone of the access networks. Moreover, the UE_A 10 is capable ofwirelessly connecting to the radio access network.

Moreover, a WLAN Access Network b (WLAN ANb 75) that connects to thecore network via the ePDG_A 65 and a WLAN Access Network a (WLAN ANa 75)that connects to the PGW_A, the PCRF_A 60, and the AAA_A 55 can beconfigured as access networks connectable in a WLAN access system.

Note that each device has a similar configuration to those of thedevices of the related art in a mobile communication system using EPS,and thus detailed descriptions thereof will be omitted. Each device willbe described briefly hereinafter.

The PGW_A 30 is connected to the PDN_A 5, the SGW_A 35, the ePDG_A 65,the WLAN Ana 70, the PCRF_A 60, and the AAA_A 55, and serves as a relaydevice configured to transfer user data by functioning as a gatewaydevice between the PDN_A 5 and the core network_A 90.

The SGW_A 35 is connected to the PGW 30, the MME_A 40, the LTE AN 80,the SGSN_A 42, and the UTRAN_A 20, and serves as a relay deviceconfigured to transfer user data by functioning as a gateway devicebetween the core network_A 90 and the 3GPP access network (the UTRAN_A20, the GERAN_A 25, the LTE AN_A 80).

The MME_A 40 is connected to the SGW_A 35, the LTE AN 80, and the HSS_A50, and serves as an access control device configured to performlocation information management and access control for the UE_A 10 viathe LTE AN 80. Furthermore, the core network_A 90 may include multiplelocation management devices. For example, a location management devicedifferent from the MME_A 40 may be configured. As with the MME_A 40, thelocation management device different from the MME_A 40 may be connectedto the SGW_A 35, the LTE AN 80, and the HSS_A 50.

Furthermore, in a case that multiple MMEs are included in the corenetwork_A 90, the MMEs may be connected to each other. With thisconfiguration, the context of the UE_A 10 may be transmitted and/orreceived between the MMEs.

The HSS_A 50 is connected to the MME_A 40 and the AAA_A 55 and serves asa managing node that manages subscriber information. The subscriberinformation of the HSS_A 50 is referred to during MME_A 40 accesscontrol, for example. Moreover, the HSS_A 50 may be connected to thelocation management device different from the MME_A 40.

The AAA_A 55 is connected to the PGW 30, the HSS_A 50, the PCRF_A 60,and the WLAN ANa 70, and is configured to perform access control for theUE_A 10 connected via the WLAN ANa 70.

The PCRF_A 60 is connected to the PGW_A 30, the WLAN ANa 75, the AAA_A55, and the PDN_A 5, and is configured to perform QoS management on datadelivery. For example, the PCRF_A 60 manages QoS of a communication pathbetween the UE_A 10 and the PDN_A 5.

The ePDG_A 65 is connected to the PGW 30 and the WLAN ANb 75 and isconfigured to deliver user data by functioning as a gateway devicebetween the core network_A 90 and the WLAN ANb 75.

The SGSN_A 42 is connected to the UTRAN_A 20, the GERAN_A 25, and theSGW_A 35 and is a control device for location management between a 3G/2Gaccess network (UTRAN/GERAN) and the LTE access network (E-UTRAN). Inaddition, the SGSN_A 42 has functions of: selecting the PGW and the SGW;managing a time zone of the UE; and selecting the MME at the time ofhandover to the E-UTRAN.

Additionally, as illustrated in FIG. 2(b), each radio access networkincludes devices to which the UE_A 10 is actually connected (such as abase station device and an access point device), and the like. Thedevices used in these connections can be thought of as devices adaptedto the radio access networks.

In the present embodiment, the LTE AN 80 includes the eNB_A 45. TheeNB_A 45 is a radio base station to which the UE_A 10 connects in an LTEaccess system, and the LTE AN_A 80 may include one or multiple radiobase stations.

The WLAN ANa 70 includes a WLAN APa 72 and a TWAG_A 74. The WLAN APa 72is a radio base station to which the UE_A 10 connects in the WLAN accesssystem trusted by the operator running the core network_A 90, and theWLAN ANa 70 may include one or multiple radio base stations. The TWAG_A74 serves as a gateway device between the core network_A 90 and the WLANANa 70. The WLAN APa 72 and the TWAG_A 74 may be configured as a singledevice.

Even in a case that the operator running the core network_A 90 and theoperator running the WLAN ANa 70 are different, such a configuration canbe implemented through contracts and agreements between the operators.

Furthermore, the WLAN ANb 75 is configured to include a WLAN APb 76. TheWLAN APb 76 is a radio base station to which the UE_A 10 connects in theWLAN access system in a case that no trusting relationship isestablished with the operator running the core network_A 90, and theWLAN ANb 75 may include one or multiple radio base stations.

In this manner, the WLAN ANb 75 is connected to the core network_A 90via the ePDG_A 65, which is a device included in the core network_A 90,serving as a gateway. The ePDG_A 65 has a security function for ensuringsecurity.

The UTRAN_A 20 includes a Radio Network Controller (RNC)_A 24 and an eNB(UTRAN)_A 22. The eNB (UTRAN)_A 22 is a radio base station to which theUE_A 10 connects through a UMTS Terrestrial Radio Access (UTRA), and theUTRAN_A 20 may include one or multiple radio base stations. Furthermore,the RNC_A 24 is a control unit configured to connect the core network_A90 and the eNB (UTRAN)_A 22, and the UTRAN_A 20 may include one ormultiple RNCs. Moreover, the RNC_A 24 may be connected to one ormultiple eNBs (UTRANs)_A 22. In addition, the RNC_A 24 may be connectedto a radio base station (Base Station Subsystem (BSS)_A 26) included inthe GERAN_A 25.

The GERAN_A 25 includes the BSS_A 26. The BSS_A 26 is a radio basestation to which the UE_A 10 connects through GSM (trade name)/EDGERadio Access (GERA), and the GERAN_A 25 may be constituted of one ormultiple radio base station BSSs. Furthermore, the multiple BSSs may beconnected to each other. Moreover, the BSS_A 26 may be connected to theRNC_A 24.

Next, a second example of a configuration of the core network_A 90 willbe described. For example, in a case that the UE_A 10 is a CIoTterminal, the core network_A 90 may be configured as illustrated in FIG.3(a). The core network_A 90 in FIG. 3(a) includes a CIoT Serving GatewayNode (C-SGN)_A 95 and the HSS_A 50. Note that in the same manner asFIGS. 2A and 2B, in order for the core network_A 90 to provideconnectivity to an access network other than LTE, the core network_A 90may include the AAA_A 55 and/or the PCRF_A 60 and/or the ePDG_A 65and/or SGSN_A 42.

A C-SGN_A 95 may be a node that has roles of the MME_A 40, the SGW_A 35,and the PGW_A 30 in FIGS. 2A and 2B. The C-SGN_A 95 may be a node forthe CIoT terminal.

In other words, the C-SGN_A 95 may have a gateway device functionbetween the PDN_A and the core network_A 90, a gateway device functionbetween the core network_A 90 and a CIOT AN_A 100, and a locationmanagement function of the UE_A 10.

As illustrated in the drawing, the UE_A 10 connects to the corenetwork_A 90 through the radio access network CIOT AN_A 100.

FIG. 3B illustrates the configuration of the CIOT AN_A 100. Asillustrated in the drawing, the CIOT AN_A 100 may be configuredincluding the eNB_A 45. The eNB_A 45 included in the CIOT AN_A 100 maybe the same base station as the eNB_A 45 included in the LTE AN_A 80.Alternatively, the eNB_A 45 included in the CIOT AN_A 100 may be a basestation for CIoT, which is different from the eNB_A 45 included in theLTE AN_A 80.

A first core network and/or a second core network may be constituted bya system optimized for IoT.

Note that herein, the UE_A 10 being connected to radio access networksrefers to the UE_A 10 being connected to a base station device, anaccess point, or the like included in each of the radio access networks,and data, signals, and the like being transmitted and/or received alsopass through those base station devices, access points, or the like.

1.2. Device Configuration

The configuration of each device will be described below.

1.2.1. eNB Configuration

The configuration of the eNB_A 45 will be described below. FIG. 4(a)illustrates the device configuration of the eNB_A 45. As illustrated inthe drawing, the eNB_A 45 includes a network connection unit_A 420, acontrol unit_A 400, and a storage unit_A 440. The network connectionunit_A 420 and the storage unit_A 440 are connected to the controlunit_A 400 via a bus.

The control unit_A 400 is a function unit for controlling the eNB_A 45.The control unit_A 400 implements various processes by reading outvarious programs stored in the storage unit_A 440 and executing theprograms.

The network connection unit_A 420 is a function unit through which theeNB_A 45 connects to the MME_A 40 and/or the SGW_A 35 or the C-SGN_A 95.Furthermore, the network connection unit_A 420 is a transmission and/orreception function unit through which the eNB_A 45 transmits and/orreceives the user data and/or control data to or from the MME_A 40and/or the SGW_A 35 or the C-SGN_A 95.

The storage unit_A 440 is a function unit for storing programs, data,and the like necessary for each operation of the eNB_A 45. A storageunit 640 is constituted of, for example, a semiconductor memory, a HardDisk Drive (HDD), or the like.

The storage unit_A 440 may store at least identification informationand/or control information and/or a flag and/or a parameter included ina control message transmitted and/or received in an attach procedure anda data transmission procedure, which will be described in 1.3 and 1.4.

Furthermore, the eNB_A 45 includes a transmission and/or reception unittransmitting and/or receiving to or from the UE_A 10 the controlinformation and/or the user data. Furthermore, an external antenna isconnected to the transmission and/or reception unit.

1.2.2. MME Configuration

The configuration of the MME_A 40 will be described below. FIG. 6(a)illustrates the device configuration of the MME_A 40. As illustrated inthe drawing, the MME_A 40 includes a network connection unit_B 620, acontrol unit_B 600, and a storage unit_B 640. The network connectionunit_B 620 and the storage unit_B 640 are connected to the controlunit_B 600 via a bus.

The control unit_B 600 is a function unit for controlling the MME_A 40.The control unit_B 600 implements various processes by reading out andexecuting various programs stored in the storage unit_B 640.

The network connection unit_B 620 is a function unit through which theMME_A 40 connects to the HSS_A 50 and/or the SGW_A 35. Furthermore, thenetwork connection unit_B 620 is a transmission and/or receptionfunction unit through which the MME_A 40 transmits and/or receives to orfrom the HSS_A 50 and/or the SGW_A 35 the user data and/or control data.

The storage unit_B 640 is a function unit for storing programs, data,and the like necessary for each operation of the MME_A 40. The storageunit_B 640 is constituted of, for example, a semiconductor memory, aHard Disk Drive (HDD), or the like.

The storage unit_B 640 may store at least the identification informationand/or the control information and/or the flag and/or the parameterincluded in the control message transmitted and/or received in theattach procedure and the data transmission procedure, which will bedescribed in 1.3 and 1.4.

As illustrated in the drawing, the storage unit_B 640 stores an MMEcontext 642, a security context 648, and MME emergency configurationdata 650. Note that the MME context includes an MM context and an EPSbearer context. Alternatively, the MME context may include an EMMcontext and an ESM context. The MM context may be the EMM context, theEPS bearer context may be the ESM context.

FIG. 7(b), FIG. 8(b), and FIG. 9 (b) illustrate information elements ofthe MME context stored for each UE. As illustrated in the drawings, theMME context stored for each UE includes an IMSI, anIMSI-unauthenticated-indicator, an MSISDN, an MM State, a GUTI, an MEIdentity, a Tracking Area List, a TAI of last TAU, an E-UTRAN CellGlobal Identity (ECGI), an E-UTRAN Cell Identity Age, a CSG ID, a CSGmembership, an Access mode, an Authentication Vector, a UE Radio AccessCapability, MS Classmark 2, MS Classmark 3, Supported Codecs, a UENetwork Capability, an MS Network Capability, UE Specific DRXParameters, a Selected NAS Algorithm, an eKSI, a K_ASME, NAS Keys andCOUNT, a Selected CN operator ID, a Recovery, an Access Restriction, anODB for PS parameters, an APN-OI Replacement, an MME IP address for S11,an MME TEID for S11, an S-GW IP address for S11/S4, an S GW TEID forS11/S4, an SGSN IP address for S3, an SGSN TEID for S3, an eNodeBAddress in Use for S1-MME, an eNB UE S1AP ID, an MME UE S1AP ID, aSubscribed UE-AMBR, a UE-AMBR, EPS Subscribed Charging Characteristics,a Subscribed RFSP Index, an RFSP Index in Use, a Trace reference, aTrace type, a Trigger ID, an OMC identity, a URRP-MME, CSG SubscriptionData, a LIPA Allowed, a Subscribed Periodic RAU/TAU Timer, an MPS CSpriority, an MPS EPS priority, a Voice Support Match Indicator, and aHomogenous Support of IMS Voice over PS Sessions.

The IMSI is permanent identification information of a user. The IMSI isidentical to the IMSI stored in the HSS_A 50.

The IMSI-unauthenticated-indicator is instruction information indicatingthat this IMSI is not authenticated.

MSISDN represents the phone number of UE. The MSISDN is indicated by thestorage unit of the HSS_A 50.

The MM State indicates a mobility management state of the MME. Thismanagement information indicates an ECM-IDLE state in which a connectionbetween the eNB and the core network is released, an ECM-CONNECTED statein which the connection between the eNB and the core network is notreleased, or an EMM-DEREGISTERED state in which the MME does not storethe location information of the UE.

The Globally Unique Temporary Identity (GUTI) is temporaryidentification information about the UE. The GUTI includes theidentification information about the MME (Globally Unique MME Identifier(GUMMEI)) and the identification information about the UE in a specificMME (M-TMSI).

The ME Identity is an ID of the UE, and may be the IMEI/IMISV, forexample.

The Tracking Area List is a list of the tracking area identificationinformation which is assigned to the UE.

The TAI of last TAU is the tracking area identification informationindicated by a recent tracking area update procedure.

The ECGI is cell identification information of the recent UE known bythe MME_A 40.

The E-UTRAN Cell Identity Age indicates the elapsed time since the MMEacquires the ECGI.

The CSG ID is identification information of a Closed Subscriber Group(CSG), in which the UE recently operates, known by the MME.

The CSG membership is member information of the CSG of the recent UEknown by the MME. The CSG membership indicates whether the UE is the CSGmember.

The Access mode is an access mode of a cell identified by the ECGI, maybe identification information indicating that the ECGI is a hybrid whichallows access to both the UEs which is the CSG and is not the CSG

The Authentication Vector indicates a temporary Authentication and KeyAgreement (AKA) of a specific UE followed by the MME. The AuthenticationVector includes a random value RAND used for authentication, anexpectation response XRES, a key K_ASME, and a language (token) AUTNauthenticated by the network.

The UE Radio Access Capability is identification information indicatinga radio access capability of the UE.

MS Classmark 2 is a classification symbol (Classmark) of a core networkof a CS domain of 3G/2G (UTRAN/GERAN). MS Classmark 2 is used in a casethat the UE supports a Single Radio Voice Call Continuit (SRVCC) for theGERAN or the UTRAN.

MS Classmark 3 is a classification symbol (Classmark) of a radio networkof the CS domain of the GERAN. MS Classmark 3 is used in a case that theUE supports the Single Radio Voice Call Continuit (SRVCC) for the GERAN.

The Supported Codecs are a code list supported by the CS domain. Thislist is used in a case that the UE supports SRVCC for the GERAN or theUTRAN.

The UE Network Capability includes an algorithm of security supported bythe UE and a key derivative function.

The MS Network Capability is information including at least one kind ofinformation necessary for the SGSN to the UE having the GERAN and/orUTRAN function.

The UE Specific DRX Parameters are parameters used for determining aDiscontinuous Reception (DRX) cycle length of the UE. Here, DRX is afunction for changing the UE to a low-power-consumption mode in a casethat there is no communication in a certain period of time, in order toreduce power consumption of a battery of the UE as much as possible.

The Selected NAS Algorithm is a selected security algorithm of aNon-Access Stream (NAS).

The eKSI is a key set indicating the K_ASME. The eKSI may indicatewhether a security key acquired by a security authentication of theUTRAN or the E-UTRAN is used.

The K_ASME is a key for E-UTRAN key hierarchy generated based on aCipher Key (CK) and an Integrity Key (IK).

The NAS Keys and COUNT includes a key K_NASint, a key K_NASenc, and aNAS COUNT parameter. The key K_NASint is a key for encryption betweenthe UE and the MME, the key K_NASenc is a key for security protectionbetween the UE and the MME. Additionally, the NAS COUNT is a count whichstarts a count in a case that a new key by which security between the UEand the MME is established is configured.

The Selected CN operator ID is identification information, which is usedfor sharing the network among operators, of a selected core networkoperator.

The Recovery is identification information indicating whether the HSSperforms database recovery.

The Access Restriction is registration information for accessrestriction.

The ODB for PS parameters indicates a state of an operator determinedbarring (ODB). Here, ODB is an access rule determined by the networkoperator (operator).

The APN-OI Replacement is a domain name substituting for APN when PGWFQDN is constructed in order to execute a DNS resolution. Thissubstitute domain name is applied to all APNs.

The MME IP address for S11 is an IP address of the MME used for aninterface with the SGW.

The MME TEID for S11 is a Tunnel Endpoint Identifier (TEID) used for theinterface with the SGW.

The S-GW IP address for S11/S4 is an IP address of the SGW used for aninterface between the MME and the SGW or between the SGSN and the MME.

The S GW TEID for S11/S4 is a TEID of the SGW used for the interfacebetween the MME and the SGW or between the SGSN and the MME.

The SGSN IP address for S3 is an IP address of the SGSN used for theinterface between the MME and the SGSN.

The SGSN TEID for S3 is a TEID of the SGSN used for the interfacebetween the MME and the SGSN.

The eNodeB Address in Use for S1-MME is an IP address of the eNBrecently used for an interface between the MME and the eNB.

The eNB UE S1AP ID is identification information of the UE in the eNB.

The MME UE S1AP ID is identification information of the UE in the MME.

The Subscribed UE-AMBR indicates the maximum value of a Maximum Bit Rate(MBR) of uplink communication and downlink communication for sharing allNon-Guaranteed Bit Rate (GBR) bearers (non-guaranteed bearers) inaccordance with user registration information.

The UE-AMBR indicates the maximum value of the MBR of the uplinkcommunication and the downlink communication which are recently used forsharing all the Non-GBR bearers (non-guaranteed bearers).

The EPS Subscribed Charging Characteristics indicate a chargingperformance of the UE. For example, the EPS Subscribed ChargingCharacteristics may indicate registration information such as normal,prepaid, a flat rate, hot billing, or the like.

The Subscribed RFSP Index is an index for a specific RRM configurationin the E-UTRAN acquired from the HSS.

The RFSP Index in Use is an index for the specific RRM configuration inthe E-UTRAN which is recently used.

The Trace reference is identification information for identifying aspecific trace record or a record set.

The Trace type indicates a type of the trace. For example, the Tracetype may indicate a type traced by the HSS and/or a type traced by theMME, the SGW, or the PGW.

The Trigger ID is identification information for identifying aconstituent element for which the trace starts.

The OMC Identity is identification information for identifying the OMCwhich receives the record of the trace.

The URRP-MME is identification information indicating that the HSSrequests UE activity notification from the MME.

The CSG Subscription Data are a relevant list of a PLMN (VPLMN) CSG IDof a roaming destination and an equivalent PLMN of the roamingdestination. The CSG Subscription Data may be associated with anexpiration date indicating an expiration date of the CSG ID and anabsent expiration date indicating that there is no expiration date foreach CSG ID. The CSG ID may be used for a specific PDN connectionthrough LIPA.

The LIPA Allowed indicates whether the UE is allowed to use LIPA in thisPLMN The Subscribed Periodic RAU/TAU Timer is a timer of a periodic RAUand/or TAU.

The MPS CS priority indicates that the UE is registered in eMLPP or a1×RTT priority service in the CS domain.

The MPS EPS priority is identification information indicating that theUE is registered in MPS in the EPS domain.

The Voice Support Match Indicator indicates whether a radio capabilityof the UE is compatible with the network configuration. For example, theVoice Support Match Indicator indicates whether the SRVCC support by theUE matches the support for voice call by the network.

The Homogenous Support of IMS Voice over PS Sessions for MME isinstruction information indicating, for each UE, whether an IMS voicecall on a PS session is supported. The Homogenous Support of IMS Voiceover PS Sessions for MME includes “Supported” in which an IP MultimediaSubsystem (IMS) voice call on a Packet Switched (PS: line switching)session in all the Tracking Areas (TAs) managed by the MME is supported,and “Not Supported” indicating a case where there is no TA in which theIMS voice call on the PS session is supported. Additionally, the MMEdoes not notify the HSS of this instruction information, in a case thatthe IMS voice call on the PS session is not uniformly supported (the TAin which the support is performed and the TA in which the support is notperformed are both present in the MME), and in a case that it is notclear whether to be supported.

FIG. 10(c) illustrates information elements included in the MME contextstored in a transmittable and/or receivable state. The transmittableand/or receivable state is described later. At the time of establishinga PDN connection, the MME to be stored in the transmittable and/orreceivable state may be stored for each PDN connection. As illustratedin the drawing, the MME context stored in the transmittable and/orreceivable state includes an APN in Use, an APN Restriction, an APNSubscribed, a PDN Type, an IP Address, EPS PDN Charging Characteristics,an APN-OI Replacement, SIPTO permissions, a Local Home Network ID, LIPApermissions, a WLAN offloadability, a VPLMN Address Allowed, a PDN GWAddress in Use (control information), a PDN GW TEID for S5/S8 (controlinformation), an MS Info Change Reporting Action, a CSG InformationReporting Action, a Presence Reporting Area Action, an EPS subscribedQoS profile, a Subscribed APN-AMBR, an APN-AMBR, a PDN GW GRE Key foruplink traffic (user data), a Default bearer, and a low access priority.

The APN in Use indicates APN which is recently used. This APN includesidentification information about the APN network and identificationinformation about a default operator.

The APN Restriction indicates a restriction on a combination of an APNtype to APN associated with this bearer context. In other words, the APNRestriction is information for restricting the number of APNs and thetype of APNs which can be established.

The APN Subscribed refers to a registration APN received from the HSS.

The PDN Type indicates the type of the IP address. The PDN Typeindicates IPv4, IPv6, or IPv4v6, for example.

The IP Address indicates an IPv4 address or an IPv6 Prefix. Note thatthe IP address may store both the IPv4 and IPv6 prefixes.

The EPS PDN Charging Characteristics indicate a charging performance.The EPS PDN Charging Characteristics may indicate, for example, normal,prepaid, a flat rate, or hot billing.

The APN-OI Replacement is a proxy domain name of APN having the samerole as that of the APN-OI Replacement, registered for each UE. Notethat the APN-OI Replacement has a higher priority than that of theAPN-OI Replacement for each UE.

The SIPTO permissions indicate permission information to a Selected IPTraffic Offload (SIPTO) of traffic using this APN. Specifically, theSIPTO permissions identify a prohibition of the use of SIPTO, permissionof the use of SIPTO in the network excluding the local network,permission of the use of SIPTO in the network including the localnetwork, or permission of the use of SIPTO only in the local network.

The Local Home Network ID indicates identification information of a homenetwork to which the base station belongs, in a case that SIPTO(SIPTO@LN) using the local network can be used.

The LIPA permissions are identification information indicating whetherthis PDN can access through LIPA. Specifically, the LIPA permissions maybe an LIPA-prohibited which does not allow LIPA, an LIPA-only whichallows only LIPA, or an LIPA-conditional which allows LIPA depending ona condition.

The WLAN offload ability is identification information indicatingwhether traffic connected through this APN can perform offload to thewireless LAN by utilizing a cooperative function between the wirelessLAN and 3GPP, or maintains the 3GPP connection. The WLAN offload abilitymay vary for each RAT type. Specifically, different WLAN offloadabilities may be present for LTE (E-UTRA) and 3G (UTRA).

The VPLMN Address Allowed indicates whether a connection in which the UEuses this APN is allowed to use only an HPLMN domain (IP address) PGW inPLMN (VPLMN) of the roaming destination or allowed to use additionallythe PGW in the VPLMN domain The PDN GW Address in Use (controlinformation) indicates a recent IP address of the PGW. This address isused when a control signal is transmitted.

The PDN GW TEID for S5/S8 (control information) is a TEID used fortransmission and/or reception of the control information in an interface(S5/S8) between the SGW and the PGW.

The MS Info Change Reporting Action is an information element indicatingthat it is necessary to notify the PGW of user location informationbeing changed.

The CSG Information Reporting Action is an information elementindicating that it is necessary to notify the PGW of CSG informationbeing changed.

The Presence Reporting Area Action indicates necessity of notificationof the change as to whether the UE is present in a Presence ReportingArea. This information element separates into identification informationof the presence reporting area and an element included in the presencereporting area.

The EPS subscribed QoS profile indicates a QoS parameter to a defaultbearer at a bearer level.

The Subscribed APN-AMBR indicates the maximum value of the Maximum BitRate (MBR) of the uplink communication and the downlink communicationfor sharing all the Non-GBR bearers (non-guaranteed bearers) establishedfor this APN in accordance with the user registration information.

The APN-AMBR indicates the maximum value of the Maximum Bit Rate (MBR)of the uplink communication and the downlink communication for sharingall the Non-GBR bearers (non-guaranteed bearers) established for thisAPN, which has been determined by the PGW.

The PDN GW GRE Key for uplink traffic (user data) is a Generic RoutingEncapsulation (GRE) key for the uplink communication of the user data ofthe interface between the SGW and the PGW.

The Default bearer is EPS bearer identification information foridentifying a default bearer in the PDN connection.

The low access priority indicates that the UE requests a low accesspriority, when the PDN connection is opened.

FIG. 11(d) illustrates the MME context stored for each bearer. Asillustrated in the drawing, the MME context stored for each bearerincludes an EPS Bearer ID, a TI, an S-GW IP address for S1-u, an S-GWTEID for S1u, a PDN GW TEID for S5/S8, a PDN GW IP address for S5/S8, anEPS bearer QoS, and a TFT.

The EPS Bearer ID is the only identification information for identifyingthe EPS bearer for a UE connection via the E-UTRAN.

The TI is an abbreviation of a “Transaction Identifier”, and isidentification information identifying a bidirectional message flow(Transaction).

The S-GW IP address for S1-u is an IP address of the SGW used for aninterface between the eNB and the SGW.

The S-GW TEID for S1u is a TEID of the SGW used for the interfacebetween the eNB and the SGW.

The PDN GW TEID for S5/S8 is a TEID of the PGW for user datatransmission in the interface between the SGW and the PGW.

The PDN GW IP address for S5/S8 is an IP address of the PGW for userdata transmission in the interface between the SGW and the PGW.

The EPS bearer QoS includes a QoS Class Identifier (QCI) and anAllocation and Retention Priority (ARP). QCI indicates a class to whichthe QoS belongs. QoS can be classified in accordance with presence orabsence of band control, an allowable delay time, a packet loss rate, orthe like. The QCI includes information indicating the priority. ARP isinformation representing a priority relating to maintaining the bearer.

The TFT is an abbreviation of a “Traffic Flow Template”, and indicatesall packet filters associated with the EPS bearer.

Here, the information elements included in the MME context illustratedin FIG. 7 to FIG. 11 are included in either the MM context 644 or theEPS bearer context 646. For example, the MME context for each bearerillustrated in FIG. 11(d) may be stored in the EPS bearer context, andthe other information elements may be stored in the MM context.Alternatively, the MME context stored in the transmittable and/orreceivable state as illustrated in FIG. 10(c) and the MME context foreach bearer illustrated in FIG. 11(d) may be stored in the EPS bearercontext, and the other information elements may be stored in the MMcontext.

As illustrated in FIG. 6(a), the storage unit_B 640 of the MME may storethe security context 648. FIG. 12(e) illustrates information elementsincluded in the security context 648.

As illustrated in the drawing, the security context includes an EPS ASsecurity context and an EPS NAS security context. The EPS AS securitycontext is a context relating to security of an access stratum (AccessStream (AS)), the EPS NAS security context is a context relating tosecurity of a non-access stratum (Non-Access Stream (NAS)).

FIG. 12(f) illustrates information elements included in the EPS ASsecurity context. As illustrated in the drawing, the EPS AS securitycontext includes a cryptographic key, a Next Hop parameter (NH), a NextHop Chaining Counter parameter (NCC), and identifiers of the selected ASlevel cryptographic algorithms.

The cryptographic key is an encryption key in an access stratum.

The NH is an information element determined from the K_ASME. The NH isan information element for enabling a forward security.

The NCC is an information element associated with the NH. The NCCrepresents the number of occurrences of handovers in a verticaldirection changing the network.

The identifiers of the selected AS level cryptographic algorithms areidentification information of a selected encryption algorithm.

FIG. 12(g) illustrates information elements included in the EPS NASsecurity context. As illustrated in the drawing, the EPS NAS securitycontext may include the K_ASME, a UE Security capability, and the NASCOUNT.

The K_ASME is a key for E-UTRAN key hierarchy generated based on thekeys CK and IK.

The UE Security capability is a set of identification informationcorresponding to a cipher and an algorithm used by the UE. Thisinformation includes information for the access stratum and informationfor the non-access stratum. Furthermore, in a case that the UE supportsaccess to the UTRAN/GERAN, this information includes information for theUTRAN/GERAN.

The NAS COUN is a counter indicating the time during which the K_ASME isoperating.

The security context 648 may be included in the MME context 642.Additionally, as illustrated in FIG. 6(a), the security context 648 andthe MME context 642 may be separately present.

FIG. 12(h) illustrates information elements stored in the MME emergencyconfiguration data 650. The MME emergency configuration data areinformation which is used instead of registration information of the UEacquired from the HSS. As illustrated in the drawing, the MME emergencyconfiguration data 650 include an Emergency Access Point Name (em APN),an Emergency QoS profile, an Emergency APN-AMBR, an Emergency PDN GWidentity, and a Non-3GPP HO Emergency PDN GW identity.

The em APN indicates an access point name used for the PDN connectionfor emergency.

The Emergency QoS profile indicates QoS of the default bearer of em APNat a bearer level.

The Emergency APN-AMBR indicates the maximum value of the MBR of theuplink communication and the downlink communication for sharing theNon-GBR bearers (non-guaranteed bearers) established for em APN. Thisvalue is determined by the PGW.

The Emergency PDN GW identity is identification information of the PGWstatically configured to em APN. This identification information may bean FQDN or an IP address.

The Non-3GPP HO Emergency PDN GW identity is identification informationof the PGW statically configured to em APN, in a case that the PLMNsupports a handover to an access network other than 3GPP. Thisidentification information may be an FQDN or an IP address.

Furthermore, the MME_A 40 may manage a connection state with respect tothe UE while synchronizing with the UE.

1.2.3. SGW Configuration

Hereinafter, the configuration of the SGW_A 35 will be described. FIG.13(a) illustrates the device configuration of the SGW_A 35. Asillustrated in the drawing, the SGW_A 35 includes a network connectionunit_C 1320, a control unit_C 1300, and a storage unit_C 1340. Thenetwork connection unit_C 1320 and the storage unit_C 1340 are connectedto the control unit_C 1300 via a bus.

The control unit_C 1300 is a function unit for controlling the SGW_A 35.The control unit_C 1300 implements various processes by reading out andexecuting various programs stored in the storage unit_C 1340.

The network connection unit_C 1320 is a function unit through which theSGW_A 35 connects to the MME_A 40 and/or the PGW_A 30 and/or SGSN_A 42.Furthermore, the network connection unit_C 1320 is a transmission and/orreception function unit through which the SGW_A 35 transmits and/orreceives to or from the MME_A 40 and/or the PGW_A 30 and/or SGSN_A 42the user data and/or control data.

The storage unit_C 1340 is a function unit for storing programs, data,and the like necessary for each operation of the SGW_A 35. The storageunit_C 1340 is constituted of, for example, a semiconductor memory, aHard Disk Drive (HDD), or the like.

The storage unit_C 1340 may store at least the identificationinformation and/or the control information and/or the flag and/or theparameter included in the control message transmitted and/or received inthe attach procedure and the data transmission procedure, which will bedescribed in 1.3 and 1.4.

As illustrated in the drawing, the storage unit_C 1340 stores an EPSbearer context 1342. Note that the EPS bearer context includes an EPSbearer context stored for each UE, an EPS bearer context stored for eachPDN, and an EPS bearer context stored for each bearer.

FIG. 14(b) illustrates information elements of the EPS bearer contextstored for each UE. As illustrated in FIG. 14(b), the EPS bearer contextstored for each UE includes an IMSI, an MSI-unauthenticated-indicator,an ME Identity, an MSISDN, a Selected CN operator id, an MME TEID forS11, an MME IP address for S11, an S-GW TEID for S11/S4, an S-GW IPaddress for S11/S4, an SGSN IP address for S4, an SGSN TEID for S4, aTrace reference, a Trace type, a Trigger ID, an OMC identity, a Lastknown Cell Id, and a Last known Cell Id age.

The IMSI is permanent identification information of a user. The IMSI isidentical to the IMSI in the HSS_A 50.

The IMSI-unauthenticated-indicator is instruction information indicatingthat this IMSI is not authenticated.

The ME Identity is identification information of the UE, and may be theIMEI/IMISV, for example.

The MSISDN represents a basic phone number of the UE. The MSISDN isindicated by the storage unit of the HSS_A 50.

The Selected CN operator id is identification information, which is usedfor sharing the network among operators, of a selected core networkoperator.

The MME TEID for S11 is a TEID of the MME used for the interface betweenthe MME and the SGW.

The MME IP address for S11 is an IP address of the MME used for theinterface between the MME and the SGW.

The S-GW TEID for S11/S4 is a TEID of the SGW used for the interfacebetween the MME and the SGW, or the interface between the SGSN and theSGW.

The S-GW IP address for S11/S4 is an IP address of the SGW used for theinterface between the MME and the SGW, or the interface between the SGSNand the SGW.

The SGSN IP address for S4 is an IP address of the SGSN used for theinterface between the SGSN and the SGW.

The SGSN TEID for S4 is a TEID of the SGSN used for the interfacebetween the SGSN and the SGW.

The Trace reference is identification information for identifying aspecific trace record or a record set.

The Trace Type indicates a type of the trace. For example, the Tracetype may indicate a type traced by the HSS and/or a type traced by theMME, the SGW, or the PGW.

The Trigger ID is identification information for identifying aconstituent element for which the trace starts.

The OMC Identity is identification information for identifying the OMCwhich receives the record of the trace.

The Last known Cell ID is recent location information of the UE notifiedby the network.

The Last known Cell ID age is information indicating the period from thetime when the Last known Cell ID is stored to the present.

Furthermore, the EPS bearer context includes an EPS bearer contextstored in the transmittable and/or receivable state. The transmittableand/or receivable state is described later. At the time of establishinga PDN connection, the EPS bearer context to be stored in thetransmittable and/or receivable state may be stored for each PDNconnection. FIG. 15(c) illustrates the EPS bearer context stored in thetransmittable and/or receivable state. As illustrated in the drawing,the EPS bearer context stored in the transmittable and/or receivablestate includes an APN in Use, EPS PDN Charging Characteristics, a P-GWAddress in Use (control information), a P-GW TEID for S5/S8 (controlinformation), a P-GW Address in Use (user data), a P-GW GRE Key foruplink (user data), an S-GW IP address for S5/S8 (control information),an S-GW TEID for S5/S8 (control information), an S GW Address in Use(user data), a S-GW GRE Key for downlink traffic (user data), and aDefault Bearer.

The APN in Use indicates APN which is recently used. This APN includesidentification information about the APN network and identificationinformation about a default operator. Additionally, this information isinformation acquired from the MME or the SGSN.

The EPS PDN Charging Characteristics indicate a charging performance.The EPS PDN Charging Characteristics may indicate, for example, normal,prepaid, a flat rate, or hot billing.

The P-GW Address in Use (control information) is an IP address of thePGW used when the SGW recently transmits the control information.

The P-GW TEID for S5/S8 (control information) is a TEID of the PGW usedfor transmission of the control information in the interface between theSGW and the PGW.

The P-GW Address in Use (user data) is an IP address of the PGW usedwhen the SGW recently transmits the user data.

The P-GW GRE Key for uplink (user data) is the GRE key for the uplinkcommunication of the user data of the interface between the SGW and thePGW.

The S-GW IP address for S5/S8 (control information) is an IP address ofthe SGW used for the interface of the control information between theSGW and the PGW.

The S-GW TEID for S5/S8 (control information) is a TEID of the SGW usedfor the interface of the control information between the GW and the PGW.

The S GW Address in Use (user data) is an IP address of the SGW which isrecently used when the SGW transmits the user data.

The S-GW GRE Key for downlink traffic (user data) is the GRE key of theuplink communication used for the interface of the user data between theSGW and the PGW.

The Default Bearer is identification information for identifying adefault bearer in the PDN connection at the time of establishing the PDNconnection.

Furthermore, the EPS bearer context of the SGW includes the EPS bearercontext for each bearer. FIG. 15(d) illustrates the EPS bearer contextfor each bearer. As illustrated in the drawing, the EPS bearer contextfor each bearer includes an EPS Bearer Id, a TFT, a P-GW Address in Use(user data), a P-GW TEID for S5/S8 (user data), an S-GW IP address forS5/S8 (user data), an S-GW TEID for S5/S8 (user data), an S-GW IPaddress for S1-u, S12 and S4 (user data), an S-GW TEID for S1-u, S12 andS4 (user data), an eNodeB IP address for S1-u, an eNodeB TEID for S1-u,an RNC IP address for S12, an RNC TEID for S12, an SGSN IP address forS4 (user data), an SGSN TEID for S4 (user data), an EPS Bearer QoS, anda Charging Id.

The EPS Bearer Id is the only identification information identifying theEPS bearer for the UE connection via the E-UTRAN. That is, the EPSBearer Id is identification information for identifying the bearer.

The TFT indicates all the packet filters associated with the EPS bearer.

The P-GW Address in Use (user data) is an IP address of the PGW which isrecently used for transmission of the user data in the interface betweenthe SGW and the PGW.

The P-GW TEID for S5/S8 (user data) is a TEID of the PGW for theinterface of the user data between the SGW and the PGW.

The S-GW IP address for S5/S8 (user data) is an IP address of the SGWfor the user data received from the PGW.

The S-GW TEID for S5/S8 (user data) is a TEID of the SGW for theinterface of the user data between the SGW and the PGW.

The S-GW IP address for S1-u, S12 and S4 (user data) is an IP address ofthe SGW used for the interface between the SGW and the 3GPP accessnetwork (the LTE access network or GERAN/UTRAN).

The S-GW TEID for S1-u, S12 and S4 (user data) is a TEID of the SGW usedfor the interface between the SGW and the 3GPP access network (the LTEaccess network or GERAN/UTRAN).

The eNodeB IP address for S1-u is an IP address of the eNB used fortransmission between the SGW and the eNB.

The eNodeB TEID for S1-u is a TEID of the eNB used for the transmissionbetween the SGW and the eNB.

The RNC IP address for S12 is an IP address of the RNC used for theinterface between the SGW and the UTRAN.

The RNC TEID for S12 is a TEID of the RNC used for the interface betweenthe SGW and the UTRAN.

The SGSN IP address for S4 (user data) is an IP address of the SGSN usedfor transmission of the user data between the SGW and the SGSN.

The SGSN TEID for S4 (user data) is a TEID of the SGSN used for thetransmission of the user data between the SGW and the SGSN.

The EPS Bearer QoS represents the QoS of this bearer, and may include anARP, a GBR, an MBR, and a QCI. Here, the ARP is information representingthe priority relating to maintaining the bearer. Additionally, theGuaranteed Bit Rate (GBR) represents a b and guaranteed bit rate, andthe Maximum Bit Rate (MBR) represents the maximum bit rate.

The QCI can be classified in accordance with presence or absence of bandcontrol, an allowable delay time, a packet loss rate, or the like. TheQCI includes information indicating the priority.

The Charging Id is identification information for recording charginggenerated in the SGW and the PGW.

1.2.4. PGW Configuration

Hereinafter, the configuration of the PGW_A 30 will be described. FIG.16(a) illustrates the device configuration of the PGW_A 30. Asillustrated in the drawing, the PGW_A 30 includes a network connectionunit_D 1620, a control unit_D 1600, and a storage unit_D 1640. Thenetwork connection unit_D 1620 and the storage unit_D 1640 are connectedto the control unit_D 1600 via a bus.

The control unit_D 1600 is a function unit for controlling the PGW_A 30.The control unit_D 1600 implements various processes by reading out andexecuting various programs stored in the storage unit_D 1640.

The network connection unit_D 1620 is a function unit through which thePGW_A 30 is connected to the SGW_A 35 and/or the PCRF_A 60 and/or theePDG_A 65 and/or the AAA_A 55 and/or the GW_A 74. The network connectionunit_D 1620 is a transmission and/or reception function unit throughwhich the PGW_A 30 transmits and/or receives to or from the SGW_A 35and/or the PCRF_A 60 and/or the ePDG_A 65 and/or the AAA_A 55 and/or theGW_A 74 the user data and/or control data.

The storage unit_D 1640 is a function unit for storing programs, data,and the like necessary for each operation of the PGW_A 30. The storageunit_D 1640 is constituted of, for example, a semiconductor memory, aHard Disk Drive (HDD), or the like.

The storage unit_D 1640 may store at least the identificationinformation and/or the control information and/or the flag and/or theparameter included in the control message transmitted and/or received inthe attach procedure and the data transmission procedure, which will bedescribed later.

As illustrated in the drawing, the storage unit_D 1640 stores an EPSbearer context 1642. Note that the EPS bearer context may be stored insuch a manner that an EPS bearer context stored for each UE, an EPSbearer context stored for each APN, an EPS bearer context stored in thetransmittable and/or receivable state, and an EPS bearer context storedfor each bearer are separately stored.

FIG. 17(b) illustrates information elements included in the EPS bearercontext stored for each UE. As illustrated in the drawing, the EPSbearer context stored for each UE includes an IMSI, anIMSI-unauthenticated-indicator, an ME Identity, an MSISDN, a Selected CNoperator id, an RAT type, a Trace reference, a Trace type, a Trigger id,and an OMC identity.

The IMSI is identification information to be assigned to a user usingthe UE.

The IMSI-unauthenticated-indicator is instruction information indicatingthat this IMSI is not authenticated.

The ME Identity is an ID of the UE, and may be the IMEI/IMISV, forexample.

The MSISDN represents a basic phone number of the UE. The MSISDN isindicated by the storage unit of the HSS_A 50.

The Selected CN operator ID is identification information, which is usedfor sharing the network among operators, of a selected core networkoperator.

The RAT type indicates a recent Radio Access Technology (RAT) of the UE.The RAT type may be, for example, the E-UTRA (LTE), the UTRA, or thelike.

The Trace reference is identification information for identifying aspecific trace record or a record set.

The Trace type indicates a type of the trace. For example, the Tracetype may indicate a type traced by the HSS and/or a type traced by theMME, the SGW, or the PGW.

The Trigger ID is identification information for identifying aconstituent element for which the trace starts.

The OMC Identity is identification information for identifying the OMCwhich receives the record of the trace.

Next, FIG. 17(c) illustrates the EPS bearer context stored for each APN.As illustrated in the drawing, the EPS bearer context stored for eachAPN of the PGW storage unit includes an APN in use and an APN-AMBR.

The APN in Use indicates APN which is recently used. This APN includesidentification information about the APN network and identificationinformation about a default operator. This information is acquired fromthe SGW.

The APN-AMBR indicates the maximum value of the Maximum Bit Rate (MBR)of the uplink communication and the downlink communication for sharingall the Non-GBR bearers (non-guaranteed bearers) established for thisAPN.

FIG. 18(d) illustrates the EPS bearer context stored in thetransmittable and/or receivable state. The transmittable and/orreceivable state is described later. At the time of establishing a PDNconnection, the EPS bearer context to be stored in the transmittableand/or receivable state may be stored for each PDN connection. Asillustrated in the drawing, the EPS bearer context stored in thetransmittable and/or receivable state includes an IP Address, a PDNtype, an S-GW Address in Use (control information), an S-GW TEID forS5/S8 (control information), an S-GW Address in Use (user data), an S-GWGRE Key for downlink traffic (user data), a P-GW IP address for S5/S8(control information), a P-GW TEID for S5/S8 (control information), aP-GW Address in Use (user data), a P-GW GRE Key for uplink traffic (userdata), an MS Info Change Reporting support indication, an MS Info ChangeReporting Action, a CSG Information Reporting Action, a PresenceReporting Area Action, a BCM, a Default Bearer, and EPS PDN ChargingCharacteristics.

The IP Address indicates an IP address assigned to the UE in thetransmittable and/or receivable state. The IP address may be an IPv4and/or IPv6 prefix.

The PDN type indicates the type of the IP address. The PDN typeindicates IPv4, IPv6, or IPv4v6, for example.

The S-GW Address in Use (control information) is an IP address of theSGW which is recently used for transmission of the control information.

The S-GW TEID for S5/S8 (control information) is a TEID of the SGW usedfor transmission and/or reception of the control information between theSGW and the PGW.

The S-GW Address in Use (user data) is an IP address of the SGW which isrecently used for transmission of the user data in the interface betweenthe SGW and the PGW.

The S-GW GRE Key for downlink traffic (user data) is the GRE key whichis assigned to be used in the downlink communication of the user datafrom the PGW to the SGW at the interface between the SGW and the PGW.

The P-GW IP address for S5/S8 (control information) is an IP address ofthe PGW used for communication of the control information.

The P-GW TEID for S5/S8 (control information) is a TEID of the PGW forcommunication of the control information which uses the interfacebetween the SGW and the PGW.

The P-GW Address in Use (user data) is an IP address of the PGW which isrecently used for transmission of the user data which uses the interfacebetween the SGW and the PGW.

The P-GW GRE Key for uplink traffic (user data) is the GRE key which isassigned for the uplink communication of the user data between the SGWand the PGW, that is, transmission of the user data from the SGW to thePGW.

The MS Info Change Reporting support indication indicates that the MMEand/or the SGSN supports a notification process of user locationinformation and/or user CSG information.

The MS Info Change Reporting Action is information indicating whetherthe MME and/or the SGSN is requested to transmit a change in the userlocation information.

The CSG Information Reporting Action is information indicating whetherthe MME and/or the SGSN is requested to transmit a change in the userCSG information. This information is separately indicated (a) for a CSGcell, (b) for a hybrid cell in which a user is a CSG member, (c) for ahybrid cell in which the user is not the CSG member, or for acombination thereof.

The Presence Reporting Area Action indicates necessity of notificationof the change as to whether the UE is present in a Presence ReportingArea. This information element separates into identification informationof the presence reporting area and an element included in the presencereporting area.

The Bearer Control Mode (BCM) indicates a control state of a bearernegotiated with respect to the GERAN/UTRAN.

The Default Bearer is identification information for identifying adefault bearer included in the PDN connection at the time ofestablishing the PDN connection.

The EPS PDN Charging Characteristics are a charging performance. Thecharging performance may indicate, for example, normal, prepaid, a flatrate, hot billing.

Furthermore, FIG. 18(e) illustrates the EPS bearer context stored foreach EPS bearer. As illustrated in the drawing, the EPS bearer contextincludes an EPS Bearer Id, a TFT, an S-GW Address in Use (user data), anS-GW TEID for S5/S8 (user data), a P-GW IP address for S5/S8 (userdata), a P-GW TEID for S5/S8 (user data), an EPS Bearer QoS, and aCharging Id.

The EPS Bearer Id is identification information identifying the accessof the UE via the E-UTRAN.

The TFT is an abbreviation of a “Traffic Flow Template”, and indicatesall packet filters associated with the EPS bearer.

The S-GW Address in Use (user data) is an IP address of the SGW which isrecently used for transmission of the user data.

The S-GW TEID for S5/S8 (user data) is a TEID of the SGW forcommunication of the user data which uses the interface between the SGWand the PGW.

The P-GW IP address for S5/S8 (user data) is an IP address of the PGWfor the user data received from the PGW.

The P-GW TEID for S5/S8 (user data) is a TEID of the PGW forcommunication of the user data between the SGW and the PGW.

The EPS Bearer QoS indicates the QoS of the bearer, and may include anARP, a GBR, an MBR, and a QCI. Here, the ARP is information representingthe priority relating to maintaining the bearer. Additionally, theGuaranteed Bit Rate (GBR) represents a band guaranteed bit rate, and theMaximum Bit Rate (MBR) represents the maximum bit rate. The QCI can beclassified in accordance with presence or absence of band control, anallowable delay time, a packet loss rate, or the like. The QCI includesinformation indicating the priority.

The Charging Id is charging identification information for identifyingthe record relating to charging generated in the SGW and the PGW.

1.2.5. C-SGN Configuration

Hereinafter, the device configuration of the C-SGN_A 95 will bedescribed. FIG. 19(a) illustrates the device configuration of theC-SGN_A 95. As illustrated in the drawing, the C-SGN_A 95 includes anetwork connection unit_E 1920, a control unit_E 1900, and a storageunit_E 1940. The network connection unit_E 1920 and the storage unit_E1940 are connected to the control unit_E 1900 via a bus.

The control unit_E 1900 is a function unit for controlling the C-SGN_A95. The control unit_E 1900 implements various processes by reading outand executing various programs stored in the storage unit_E 1940.

The network connection unit_E 1920 is a function unit through which theC-SGN_A 95 connects to the eNB_A 45 and/or the HSS_A 50 and/or the PDN_A5. The network connection unit_E 1920 is a transmission and/or receptionfunction unit through which the C-SGN_A 95 transmits and/or receives toor from the eNB_A 45 and/or the HSS_A 50 and/or the PDN_A 5 the userdata and/or control data.

The storage unit_E 1940 is a function unit for storing programs, data,and the like necessary for each operation of the C-SGN_A 95. The storageunit_E 1940 is constituted of, for example, a semiconductor memory, aHard Disk Drive (HDD), or the like.

The storage unit_E 1940 may store at least the identificationinformation and/or the control information and/or the flag and/or theparameter included in the control message transmitted and/or received inthe attach procedure and the data transmission procedure, which will bedescribed in 1.3 and 1.4.

The storage unit_E 1940 stores a context A 1942, a context B 1944, acontext C 1946, and a context D 1948 as illustrated in the drawing.

The context A 1942 may be the MME context 642 illustrated in FIG. 6(a).Additionally, the context B 1944 may be the security context 648illustrated in FIG. 6(a). Additionally, the context C 1946 may be theMME emergency configuration data 650 illustrated in FIG. 6(a).

Additionally, the context D 1948 may be the EPS bearer context 1342illustrated in FIG. 13(a). Additionally, the context E 1950 may be theEPS bearer context 1642 illustrated in FIG. 16(a).

Note that in a case that the context A 1942 to the context E 1950include the same information element, such information element may notnecessarily be redundantly stored in the storage unit_E 1940, and may bestored in any context at least.

Specifically, for example, the IMSI may be included in each of thecontext A 1942, the context D 1948, and the context E 1950, or may bestored in any context.

1.2.6. UE Configuration

FIG. 20(a) illustrates a device configuration of the UE_A 10. Asillustrated in the drawing, the UE_A 10 includes a transmission and/orreception unit 2020, a control unit 2000, and a storage unit 2040. Thetransmission and/or reception unit 2020 and the storage unit 2040 areconnected to the control unit 2000 via a bus.

The control unit 2000 is a function unit for controlling the UE_A 10.The control unit 2000 implements various processes by reading out andexecuting various programs stored in the storage unit 2040.

The transmission and/or reception unit 2020 is a function unit throughwhich the UE_A 10 connects to an IP access network via an LTE basestation. Furthermore, the external antenna 2010 is connected to thetransmission and/or reception unit 2020.

The storage unit 2040 is a function unit for storing programs, data, andthe like necessary for each operation of the UE_A 10. The storage unit2040 is constituted of, for example, a semiconductor memory, a Hard DiskDrive (HDD), or the like.

As illustrated in the drawing, the storage unit 2040 stores a UE context2042. Hereinafter, information elements stored in the storage unit 2040will be described.

FIG. 21(b) illustrates information elements included in the UE contextstored for each UE. As illustrated in the drawing, the UE context storedfor each UE includes an IMSI, an EMM State, a GUTI, an ME Identity, aTracking Area List, a last visited TAI, a Selected NAS Algorithm, aSelected AS Algorithm, an eKSI, K_ASME, NAS Keys and COUNT, a TIN, UESpecific DRX Parameters, an Allowed CSG list, and an Operator CSG list.

The IMSI is permanent identification information of a subscriber.

The EMM State indicates a mobility management state of the UE. Forexample, the EMM State may be EMM-REGISTERED in which the UE isregistered with the network (registered state) or EMM-DEREGISTERD inwhich the UE is not registered with the network (deregistered state).

GUTI is an abbreviation of “Globally Unique Temporary Identity,” and istemporary identification information on the UE. The GUTI includes theidentification information about the MME (Globally Unique MME Identifier(GUMMEI)) and the identification information about the UE in a specificMME (M-TMSI).

The ME identity is an ID of an ME, and may be the IMEI/IMISV, forexample.

The Tracking Area List is a list of the tracking area identificationinformation which is assigned to the UE.

The last visited TAI is the tracking area identification informationincluded in the Tracking Area List, and is identification information ofthe latest tracking area that the UE visits.

The Selected NAS Algorithm is a selected security algorithm of the NAS.

The Selected AS Algorithm is a selected security algorithm of the AS.

The eKSI is a key set indicating the K_ASME. The eKSI may indicatewhether a security key acquired by a security authentication of theUTRAN or the E-UTRAN is used.

The K_ASME is a key for E-UTRAN key hierarchy generated based on thekeys CK and IK.

The NAS Keys and COUNT includes the key K_NASint, the key K_NASenc, andthe NAS COUNT. The K_NASint is a key for encryption between the UE andthe MME, the K_NASenc is a key for safety protection between the UE andthe MME. Additionally, the NAS COUNT is a count which starts a count ina case that a new key by which security between the UE and the MME isestablished is configured.

The Temporary Identity used in Next update (TIN) is temporaryidentification information used in the UE in an attach procedure or alocation information update procedure (RAU/TAU).

The UE Specific DRX Parameters denote a Discontinuous Reception (DRX)cycle length of the selected UE.

The Allowed CSG list is a list of the PLMN associated with a CSG ID of amember to which the allowed UE belongs, under the control of both theuser and the operator.

The Operator CSG list is a list of the PLMN associated with the CSG IDof a member to which the allowed UE belongs, under the control of onlythe operator.

Next, FIG. 21(c) illustrates the UE context stored in the transmittableand/or receivable state. The transmittable and/or receivable state isdescribed later. At the time of establishing a PDN connection, the UEcontext to be stored in the transmittable and/or receivable state may bestored for each PDN connection. As illustrated in the drawing, the UEcontext in the transmittable and/or receivable state includes an APN inUse, an APN-AMBR, an Assigned PDN Type, an IP Address, a Default Bearer,and a WLAN offloadability.

The APN in Use is APN recently utilized. This APN may includeidentification information about the network and identificationinformation about a default operator.

The APN-AMBR indicates the maximum value of the MBR of the uplinkcommunication and the downlink communication for sharing the Non-GBRbearers (non-guaranteed bearers). The APN-AMBR is established for eachAPN.

The Assigned PDN Type is a type of the PDN assigned from the network.The Assigned PDN Type may be IPv4, IPv6, or IPv4v6, for example.

The IP Address is an IP address assigned to the UE, and may be an IPv4address or an IPv6 prefix.

The Default Bearer is EPS bearer identification information foridentifying a default bearer in the PDN connection at the time ofestablishing the PDN connection.

The WLAN offloadability is WLAN offload permission informationindicating whether offload to the WLAN using an interworking functionbetween the WLAN and the 3GPP is allowed, or the 3GPP access ismaintained.

FIG. 21(d) illustrates the UE context for each bearer stored in thestorage unit of the UE. As illustrated in the drawing, the UE contextfor each bearer includes an EPS Bearer ID, a TI, an EPS bearer QoS, anda TFT.

The EPS Bearer ID is identification information of the bearer.

The TI is an abbreviation of a “Transaction Identifier”, and isidentification information identifying a bidirectional message flow(Transaction).

The TFT is an abbreviation of a “Traffic Flow Template”, and indicatesall packet filters associated with the EPS bearer.

1.3. Description of Communication Procedure

Next, a communication procedure according to the present embodiment willbe described using FIG. 22.

The communication procedure according to the present embodiment mayinclude an attach procedure (S2200), selection processing of atransmission and/or reception means (S2202), a first transmission and/orreception procedure (S2204), a second transmission and/or receptionprocedure (S2206), and a third transmission and/or reception procedure(S2208).

The first transmission and/or reception procedure (S2204), the secondtransmission and/or reception procedure (S2206), and/or the thirdtransmission and/or reception procedure (S2208) can be omitted accordingto conditions The details of the conditions for each procedure to beperformed and processing are described below.

Here, before describing the detailed steps of each procedure, in orderto avoid redundant descriptions, terminology specific to the presentembodiment and primary identification information used in each procedurewill be described beforehand.

The connectionless communication in the present embodiment may becommunication at least performing a process in which the UE_A 10transmits a Non Access Stratum (NAS) message including data packet tothe eNB_A 45 by including in a Radio Resource Control (RRC) message.Additionally/Alternatively, the connectionless communication may becommunication transmitting and/or receiving the data packet between theUE_A 10 and the eNB_A 45 without establishing the RRC connection.Additionally/Alternatively, the connectionless communication may becommunication transmitting and/or receiving the data packet during theUE_A 10 being in the idle state.

The active mode in the present embodiment may be a mode indicating astate in which the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95establish the Data Radio Bearer (DRB) and/or the Default Bearer and/orthe PDN connection, and are capable of transmitting and/or receiving theuser data.

Note that the DRB in the present embodiment may be a communication pathsuch as a radio bearer established for transmission and/or reception ofthe user data.

The PDN connection in the present embodiment may be a connection fortransmission and/or reception of the user data, the connection beingestablished between the UE_A 10 and the C-SGN_A 95.

The idle mode in the present embodiment may be a mode indicating a statein which the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 releasethe resource of the DRB and/or the Default Bearer and/or the PDNconnection, and are not capable of transmitting and/or receiving theuser data. Note that the idle mode in the present embodiment may be amode indicating that the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A95 keep the context for the DRB and/or the Default Bearer and/or the PDNconnection.

The transmittable and/or receivable state in the present embodiment is astate capable of transmitting and/or receiving the user data between theUE_A 10 and the PDN_A 5.

In more detail, the transmittable and/or receivable state may be a statein which the UE_A 10 and/or the PDN_A 5 and/or the eNB_A 45 and/or theC-SGN_A 95 transmit and/or receive the user data.

The transmittable and/or receivable state may include a first mode, asecond mode, a third mode, and a fourth mode.

The first mode may be a mode in which the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 transmit and/or receive the user data withconnectionless.

Furthermore, the first mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 transmit and/or receive the user data without establishingan RRC connection.

Furthermore, the first mode may be a mode in which the UE_A 10 and/orthe C-SGN_A 95 transmit and/or receive the user data while beingincluded in the NAS message.

Furthermore, the first mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 transmit and/or receive the user data while being includedin the RRC message.

Furthermore, the first mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 transmit and/or receive the NAS Packet Data Unit (PDU)while being included in the RRC message. Note that the NAS PDU may be acontrol message in which the user data is included in the NAS message.

Furthermore, the first mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 transmit and/or receive the user data by using SignallingRadio Bearer (SRB).

Furthermore, the first mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 transmit and/or receive the user data by using ControlSignalling Radio Bearer (CRB).

Each of the SRB and the CRB may be a communication path such as a radiobearer used for transmission and/or reception of a control message.

Furthermore, the first mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 transmit and/or receive the user databy using a bearer for transmitting and/or receiving control information.

Note that, in a case of the first mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may transmit and/or receive the user data throughthe first transmission and/or reception procedure.

The second mode may be a mode in which the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 establish a connection to transmit and/or receivethe user data.

Furthermore, the second mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 establish an RRC connection to transmit and/or receive theuser data.

Furthermore, the second mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 establish a PDN connection totransmit and/or receive the user data.

Furthermore, the second mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 transmit and/or receive the user data by using Data RadioBearer (DRB).

Furthermore, the second mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 establish a bearer for transmittingand/or receiving the user data to transmit and/or receive the user data.

Furthermore, the second mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 establish a default bearer totransmit and/or receive the user data.

Furthermore, the second mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 keep the context even after enteringthe idle mode.

Furthermore, the second mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 can transmit and/or receive the NAS message while beingincluded in a third message in an RRC.

Note that, in a case of the second mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may transmit and/or receive the user data throughthe second transmission and/or reception procedure.

The third mode may be a mode in which the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 transmit and/or receive the user data withconnectionless, or may be a mode in which the UE_A 10 and/or the eNB_A45 and/or the C-SGN_A 95 establish a connection to transmit and/orreceive the user data.

Furthermore, the third mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 transmit and/or receive the user data without establishingan RRC connection.

Furthermore, the third mode may be a mode in which the UE_A 10 and/orthe C-SGN_A 95 transmit and/or receive the user data while beingincluded in the NAS message.

Furthermore, the third mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 transmit and/or receive the user data while being includedin the RRC message.

Furthermore, the first mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 transmit and/or receive the NAS Packet Data Unit (PDU)while being included in the RRC message.

Furthermore, the third mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 transmit and/or receive the user data by using SignallingRadio Bearer (SRB).

Furthermore, the third mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 transmit and/or receive the user data by using ControlSignalling Radio Bearer (CRB).

Furthermore, the third mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 transmit and/or receive the user databy using a bearer for transmitting and/or receiving control information.

Furthermore, the third mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 establish an RRC connection to transmit and/or receive theuser data.

Furthermore, the third mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 establish a PDN connection totransmit and/or receive the user data.

Furthermore, the third mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 transmit and/or receive the user data by using Data RadioBearer (DRB).

Furthermore, the third mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 establish a bearer for transmittingand/or receiving the user data to transmit and/or receive the user data.

Furthermore, the third mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 establish a default bearer totransmit and/or receive the user data.

Furthermore, the third mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 keep the context even after enteringthe idle mode.

Furthermore, the third mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 can transmit and/or receive the NAS message while beingincluded in the third message in the RRC.

Note that, in a case of the third mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may transmit and/or receive the user data throughthe first transmission and/or reception procedure and/or the secondtransmission and/or reception procedure.

The fourth mode may be a mode in which the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 establish a connection to transmit and/or receivethe user data.

Furthermore, the fourth mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 establish an RRC connection to transmit and/or receive theuser data.

Furthermore, the fourth mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 establish a PDN connection totransmit and/or receive the user data.

Furthermore, the fourth mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 transmit and/or receive the user data by using the DRB.

Furthermore, the fourth mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 establish a bearer for transmittingand/or receiving the user data to transmit and/or receive the user data.

Furthermore, the fourth mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 establish a default bearer totransmit and/or receive the user data.

Furthermore, the fourth mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 establish two or more default bearersto transmit and/or receive the user data.

Furthermore, the fourth mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 and/or the C-SGN_A 95 delete the context after entering theidle mode.

Furthermore, the fourth mode may be a mode in which the UE_A 10 and/orthe eNB_A 45 cannot transmit and/or receive the NAS message while beingincluded in the third message in the RRC.

Note that, in a case of the fourth mode, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 may transmit and/or receive the user data throughthe third transmission and/or reception procedure.

The first identification information in the present embodiment may beinformation indicating that the UE_A 10 performing the attach procedureis a Cellular Internet of Things (CIoT) terminal.

Additionally/Alternatively, the first identification information may beinformation indicating a type of attach that indicates an attach by theCIoT terminal. Note that the information indicating the type of attachmay be an Attach type. Moreover, an attach type indicating the attach bythe CIoT terminal may be a CIoT attach.

Additionally/Alternatively, the attach type may be information thatindicates an attach type requesting a connection to a system optimizedfor Internet of Things (IoT).

The attach by the CIoT terminal may be an attach for the purpose thatthe eNB_A 45 selects the C-SGN_A 95 optimized for CIoT and the UE_A 10connects to the selected C-SGN_A 95.

Additionally/Alternatively, the first identification information may beinformation indicating that the UE_A 10 requests to connect to thesystem optimized for CIoT and/or IoT.

Additionally/Alternatively, the first identification information may beinformation indicating that the UE_A 10 includes capability of the CIoTterminal. Note that the information indicating that the UE_A 10 includesthe capability of the CIoT terminal may be UE Capability.

Additionally/Alternatively, the first identification information may beinformation indicating that a terminal includes terminal capability fortransmitting the user data by using a radio bearer for transmittingand/or receiving a control message.

Additionally/Alternatively, the first identification information may beinformation indicating that the UE_A 10 transmits and/or receives theuser data, based on the first transmission and/or reception procedure.

Additionally/Alternatively, the first identification information may beinformation indicating a request to transmit the user data by using theradio bearer for transmitting and/or receiving the control message. Inmore detail, the first identification information may be informationindicating that the UE_A 10 requests to UE_A 10 transmission and/orreception of the user data based on the first transmission and/orreception procedure.

Additionally/Alternatively, the first identification information may beinformation indicating that the UE_A 10 requests to transmit and/orreceive the user data, based on the first transmission and/or receptionprocedure.

Additionally/Alternatively, the first identification information may beinformation indicating that the user data is transmitted and/or receivedwhile being included in the NAS message. Additionally/Alternatively, thefirst identification information may be information indicating a requestto transmit and/or receive the user data while being included in the NASmessage.

Additionally/Alternatively, the first identification information may beinformation indicating that the user data is transmitted and/or receivedwhile being included in the RRC message.

Additionally/Alternatively, the first identification information may beinformation indicating a request to transmit and/or receive the userdata while being included in the RRC message.

Additionally/Alternatively, the first identification information may beinformation indicating that the UE_A 10 and/or the eNB_A 45 transmitand/or receive the NAS Packet Data Unit (PDU) while being included inthe RRC message.

Additionally/Alternatively, the first identification information may beinformation indicating that the UE_A 10 and/or the eNB_A 45 request totransmit and/or receive the NAS Packet Data Unit (PDU) while beingincluded in the RRC message.

Note that the NAS PDU may be a control message in which the user data isincluded in the NAS message.

The second identification information in the present embodiment may beinformation indicating that an attach using information indicating atype of attach that indicates an attach by the CIoT terminal is allowed.

Additionally/Alternatively, the second identification information may beNetwork Capability Information indicating that network capability isincluded by which the user data can be transmitted and/or received usinga radio bearer for transmitting and/or receiving the control message. Inmore detail, the second identification information may be informationindicating that the C-SGN_A 95 and/or the core network_A 90 includecapability of connecting to the CIoT terminal. Note that the informationindicating that the C-SGN_A 95 and/or the core network_A 90 includecapability of connecting to the CIoT terminal may be NW Capability.

Additionally/Alternatively, the second identification information may beinformation indicating that the C-SGN_A 95 transmits and/or receives theuser data, based on the first transmission and/or reception procedure.

Additionally/Alternatively, the second identification information may beinformation indicating that user data is transmitted by using the radiobearer for transmitting and/or receiving the control message is allowed.In more detail, the second identification information may be informationindicating that the C-SGN_A 95 allows transmission and/or reception ofthe user data based on the first transmission and/or receptionprocedure.

Additionally/Alternatively, the second identification information may beinformation indicating that a connection to the system optimized for IoTis established.

The third identification information in the present embodiment may be UECapability Information indicating that network capability is included bywhich the user data can be transmitted and/or received by establishing aradio bearer for transmitting and/or receiving the user data. In moredetail, the third identification information may be the UE CapabilityInformation indicating that the UE_A 10 includes capability fortransmission and/or reception of the user data based on the secondtransmission and/or reception procedure.

Additionally/Alternatively, the third identification information may beinformation indicating that the UE_A 10 transmits and/or receives theuser data, based on the second transmission and/or reception procedure.

Additionally/Alternatively, the third identification information may beinformation indicating a request to transmit and/or receive the userdata by establishing the radio bearer for transmitting and/or receivingthe user data. In more detail, the third identification information maybe information indicating that the UE_A 10 requests to allowtransmission and/or reception of the user data based on the secondtransmission and/or reception procedure.

Additionally/Alternatively, the third identification information may beinformation indicating that the UE_A 10 requests to transmit and/orreceive the user data, based on the second transmission and/or receptionprocedure.

Additionally/Alternatively, the third identification information may beinformation indicating that the terminal capability is included by whichthe first state transition can be performed, and/or informationindicating a request to perform the first state transition. Note thatthe first state transition may be a state transition by which a state ischanged between the active state and the idle state, based on a ResumeID described later.

The fourth identification information in the present embodiment may beNetwork Capability Information indicating that network capability isincluded by which the user data can be transmitted and/or received byestablishing a radio bearer for transmitting and/or receiving the userdata. In more detail, the fourth identification information may be theNetwork Capability Information indicating that the C-SGN_A 95 and/or thecore network_A 90 include capability for transmission and/or receptionof the user data based on the second transmission and/or receptionprocedure.

Additionally/Alternatively, the fourth identification information may beinformation indicating that the C-SGN_A 95 transmits and/or receives theuser data, based on the second transmission and/or reception procedure.

Additionally/Alternatively, the fourth identification information may beinformation indicating that user data is transmitted and/or received byestablishing the radio bearer for transmitting and/or receiving the userdata is allowed. In more detail, the fourth identification informationmay be information indicating that the C-SGN_A 95 allows transmissionand/or reception of the user data based on the second transmissionand/or reception procedure.

Additionally/Alternatively, the fourth identification information may beinformation indicating that the network capability is included by whichthe first state transition can be allowed, and/or information indicatingthat performing the first state transition is allowed. Note that thefirst state transition may be a state transition by which a state ischanged between the active state and the idle state, based on the ResumeID described later.

The fifth identification information in the present embodiment may beinformation indicating that the eNB_A 45 includes capability fortransmission and/or reception of the user data based on the secondtransmission and/or reception procedure. Note that the informationindicating that the eNB_A 45 includes capability for transmission and/orreception of the user data based on the second transmission and/orreception procedure may be eNB Capability.

Additionally/Alternatively, the fifth identification information may beinformation indicating that the eNB_A 45 transmits and/or receives theuser data, based on the second transmission and/or reception procedure.

Additionally/Alternatively, the fifth identification information may beinformation indicating that the eNB_A 45 allows the user date to betransmitted and/or received, based on the second transmission and/orreception procedure.

Additionally/Alternatively, the fifth identification information may beinformation indicating that the eNB_A 45 requests to transmit and/orreceive the user data, based on the second transmission and/or receptionprocedure.

The sixth identification information in the present embodiment may beinformation indicating a type of PDN Address requested by the UE_A 10 tobe assigned. The information indicating the type of PDN Address may be aPDN Type. The PDN type may be information indicating an IPv4, may beinformation indicating an IPv6, and may be information indicating anIPv4v6.

Additionally/Alternatively, the sixth identification information may beinformation indicating that the Data Radio Bearer (DRB) and/or DefaultBearer are requested to be established in the attach procedure.

The seventh identification information in the present embodiment may beinformation indicating the PDN Address assigned by the C-SGN_A 95 to theUE_A 10. The PDN address may be an IPv4 Address, or may be an InterfaceIdentifier (Interface ID) indicated by lower 64 bit information of anIPv6 Address, or may include both the IPv4 address and the interface IDof the IPv6.

In more detail, the PDN address may be constituted by an IPv4 addressfield including the IPv4 address and/or an IPv6 address field includingthe interface ID of the IPv6.

In a case that the PDN address assigned to the UE_A 10 includes an IPv4address with all elements indicated by zero such as 0.0.0.0, and/or anyinterface ID of the IPv6, the seventh identification information may beused as information indicating that establishing the Data Radio Bearer(DRB) and/or the Default Bearer in the attach procedure is allowed, inorder that the UE_A 10 acquires an IP address.

Moreover, in a case that the PDN address assigned to the UE_A 10 is notan address with all elements indicated by zero such as 0.0.0.0 butincludes an IPv4 address used by the UE_A 10, and does not include anyinterface ID of the IPv6, the seventh identification information may beused as information indicating that the Data Radio Bearer (DRB) and/orthe Default Bearer are not established in the attach procedure, in orderthat the UE_A 10 acquires an IP address. In this case, the seventhidentification information may be used as information indicating thatacquisition of the IP address is not required after completion of theattach procedure.

In a case that all the IPv4 address field of the PDN address includeszero such as 0.0.0.0, the seventh identification information may be usedas information indicating or requesting acquisition of the IPv4 addressby using DHCP after completion of the attach procedure for the UE_A 10.

In a case that the IPv6 address field of the PDN address includes anyinterface ID of the IPv6, the seventh identification information may beused as information indicating or requesting acquisition of an IPv6prefix indicated by upper 64 bit information of an IPv6 address forcreating and/or acquiring the IPv6 address by using a stateless addressconfiguration procedure or the like after completion of the attachprocedure for the UE_A 10.

The eighth identification information in the present embodiment may beinformation indicating that the C-SGN_A 95 and/or the core network_A 90do not include capability for transmission and/or reception of the userdata based on the second transmission and/or reception procedure. Notethat the information indicating that the C-SGN_A 95 and/or the corenetwork_A 90 do not include capability for transmission and/or receptionof the user data based on the second transmission and/or receptionprocedure may be NW Capability.

Additionally/Alternatively, the eighth identification information may beinformation indicating that the C-SGN_A 95 does not perform transmissionand/or reception of the user data based on the second transmissionand/or reception procedure.

Additionally/Alternatively, the eighth identification information may beinformation indicating that the C-SGN_A 95 does not allow thetransmission and/or reception of the user data based on the secondtransmission and/or reception procedure to be performed.

The ninth identification information in the present embodiment may beinformation indicating a reason why the C-SGN_A 95 determines not toperform the transmission and/or reception of the user data based on thesecond transmission and/or reception procedure.

Additionally/Alternatively, the eighth identification information may beinformation indicating a reason why the C-SGN_A 95 determines not toallow the transmission and/or reception of the user data based on thesecond transmission and/or reception procedure to be performed.

Note that the reasons for determination not to perform the transmissionand/or reception of the user data based on the second transmissionand/or reception procedure, and/or not to allow the transmission and/orreception to be performed may be included in EMM cause.

The tenth identification information in the present embodiment may beinformation indicating that the UE_A 10 performing the detach procedureis the CIoT terminal.

Additionally/Alternatively, the tenth identification information may beinformation indicating a type of detach that indicates a detach by theCIoT terminal. Note that the information indicating the type of detachmay be a Detach type. Moreover, a detach type indicating the detach bythe CIoT terminal may be a CIoT detach.

Additionally/Alternatively, the eleventh identification information maybe the detach type requesting that a connection to the system optimizedfor IoT is released.

Additionally/Alternatively, the detach by the CIoT terminal may be adetach for the purpose of releasing the connection of the UE_A 10connected for the CIoT terminal.

Additionally/Alternatively, the tenth identification information may beinformation indicating that the UE_A 10 releases the connection in whichthe user data is transmitted and/or received based on the firsttransmission and/or reception procedure and/or the second transmissionand/or reception procedure.

Additionally/Alternatively, the tenth identification information may beinformation indicating that the UE_A 10 requests to release theconnection in which the user data is transmitted and/or received basedon the first transmission and/or reception procedure and/or the secondtransmission and/or reception procedure.

Additionally/Alternatively, the tenth identification information may beinformation indicating that the UE_A 10 requests to release theconnection to the system optimized for CIoT and/or IoT.

The transmittable and/or receivable state of the UE_A 10 performing thedetach procedure may be information indicating the first mode and/or thesecond mode and/or the third mode.

The eleventh identification information in the present embodiment may beinformation indicating that the C-SGN_A 95 performing the detachprocedure is connected to the CIoT terminal.

Additionally/Alternatively, the eleventh identification information maybe information indicating a type of detach that indicates a detach bythe CIoT terminal. Note that the information indicating the type ofdetach may be the Detach type. Moreover, the detach type indicating thedetach by the CIoT terminal may be the CIoT detach.

Note that the detach by the CIoT terminal may be a detach for thepurpose of releasing the connection of the UE_A 10 serving as the CIoTterminal.

Additionally/Alternatively, the eleventh identification information maybe the detach type requesting that a connection to the system optimizedfor IoT is released.

Additionally/Alternatively, the eleventh identification information maybe information indicating that the C-SGN_A 95 releases the connection inwhich the user data is transmitted and/or received based on the firsttransmission and/or reception procedure and/or the second transmissionand/or reception procedure.

Additionally/Alternatively, the eleventh identification information maybe information indicating that the C-SGN_A 95 requests to release theconnection in which the user data is transmitted and/or received basedon the first transmission and/or reception procedure and/or the secondtransmission and/or reception procedure.

The transmittable and/or receivable state of the C-SGN_A 95 performingthe detach procedure may be information indicating the first mode and/orthe second mode and/or the third mode.

The twelfth identification information in the present embodiment may beinformation indicating a reason why the C-SGN_A 95 determines to performthe detach procedure.

For example, a reason for the determination to perform the detachprocedure may be information indicating that the UE_A 10, the C-SGN_A95, and/or the eNB_A 45 are prohibited from being in the first modeand/or the second mode and/or the third mode of the transmittable and/orreceivable state, based on a change of subscriber information, anoperator policy, or the like. In other words, the reason may beinformation indicating that the UE_A 10, the C-SGN_A 95, and/or theeNB_A 45 are prohibited from transmitting and/or receiving the user datathrough the first transmission and/or reception procedure and/or thesecond transmission and/or reception procedure, based on a change ofsubscriber information, an operator policy, or the like.

Additionally/Alternatively, the twelfth identification information maybe information indicating a reason why the transmission and/or receptionof the user data based on the first transmission and/or receptionprocedure and/or the second transmission and/or reception procedure areprohibited.

The reason why the C-SGN_A 95 determines to perform the detachprocedure, and/or the reason why the transmission and/or reception ofthe user data based on the first transmission and/or reception procedureand/or the second transmission and/or reception procedure are prohibitedmay be included in the EMM cause.

Further, in the present embodiment, in a case that two or more kinds ofidentification information among the first to twelfth identificationinformation are transmitted while being included in the same controlmessage, each kind of identification information may be included andtransmitted, or one kind of identification information having meaningsindicated by each kind of identification information may be included inthe control message. Note that the identification information may be aninformation element configured as the flag or the parameter.

1.3.1. Attach Procedure Example

First, an example of an attach procedure will be described. Note thatthe attach procedure is a procedure which is started on the initiativeof the UE_A 10. In the attach procedure of a normal case, the attachprocedure is a procedure for the UE_A 10 to connect to a network. Inother words, the attach procedure of the normal case is a procedure forconnecting to an access network including the eNB 45, and is a procedurefor further connecting to a core network through the access network. TheUE_A 10 establishes a communication path through which the user data istransmitted and/or received with the PDN_A 5 by the attach procedure ofthe normal case. A trigger when the UE_A 10 starts the attach proceduremay be a time when the power is supplied to the terminal, or the like.Additionally, the UE_A 10 may start at an arbitrary timing in a casethat the UE_A 10 is not connected to the core network_A 90 regardless ofthe above. The UE_A 10 may enter the transmittable and/or receivablestate, based on connecting to the core network_A 90 network, and/orcompletion of the attach procedure.

Hereinafter, the details of the attach procedure of a normal case aredescribed as a first attach procedure example.

In the attach procedure of a failure system, the attach procedure is aprocedure in which the UE_A 10 has not established a connection to anetwork at the time of completion of the attach procedure. In otherwords, the attach procedure of a failure system is a procedure in whichan attempt to connect to the network by the UE_A 10 fails finally, and aprocedure in which the UE_A 10 and/or the C-SGN_A 95 reject that theUE_A 10 connects to the network. The details of an attach procedureexample of a failure system are described as a second attach procedureexample and a third attach procedure example.

1.3.1.1. First Attach Procedure Example

Hereinafter, an example of the steps of a first attach procedure will bedescribed using FIG. 23.

First, the UE_A 10 transmits an ATTACH REQUEST message to the C-SGN_A 95(S2300). Note that the UE_A 10 may transmit the ATTACH REQUEST messageto the eNB_A 45, and the transmitted ATTACH REQUEST message may betransferred to the C-SGN_A 95 via the eNB_A 45.

Additionally, the UE_A 10 may transmit a PDN connectivity requestmessage with the ATTACH REQUEST message. Hereinafter, in the descriptionof the present embodiment, the ATTACH REQUEST message is described as amessage in which the ATTACH REQUEST message and the PDN connectivityrequest message are combined. Furthermore, in the description of thepresent embodiment, in a case that an expression “identificationinformation is included in the ATTACH REQUEST message” is used, theexpression means that the identification information is included in theATTACH REQUEST message and/or the PDN connectivity request message.

The UE_A 10 may include at least the first identification informationand/or the third identification information and/or the sixthidentification information in the ATTACH REQUEST message. The UE_A 10may request a transition to the transmittable and/or receivable state bytransmitting the ATTACH REQUEST message including the firstidentification information and/or the third identification information.The eNB_A 45 may include the fifth identification information in theATTACH REQUEST message and/or a message for transferring the ATTACHREQUEST message. The eNB_A 45 may request a transition to thetransmittable and/or receivable state by transmitting the fifthidentification information while being included in the ATTACH REQUESTmessage and/or the message for transferring the ATTACH REQUEST message.

Here, the first identification information and/or the thirdidentification information and/or the sixth identification informationmay not be transmitted to the C-SGN_A 95 by being included in the ATTACHREQUEST message, and may instead be transmitted while being included ina control message different from the ATTACH REQUEST in the attachprocedure.

For example, after transmitting the ATTACH REQUEST message, the UE_A 10may perform a request of EPS Session Management (ESM) information, and atransmission and/or reception procedure of a control message whichresponds based on the request (S2302).

To be more specific, the C-SGN_A 95 transmits an ESM request message tothe UE_A 10. The UE_A 10 receives the ESM request message, and transmitsa response message to the C-SGN_A 95. At this time, the UE_A 10 maytransmit the first identification information and/or the thirdidentification information and/or the sixth identification informationwhile being included in the response message.

Here, the UE_A 10 may encrypt and transmit the ESM response message.Furthermore, the UE_A 10 may receive information for encrypting the ESMresponse message from the C-SGN_A 95. The C-SGN_A 95 may transmitinformation for encrypting the NAS message to the UE_A 10 with thereception of the ATTACH REQUEST message. Note that the NAS message forwhich the information for encrypting the NAS message is transmitted maybe a Security Mode Command message.

The C-SGN_A 95 receives the ATTACH REQUEST message. Furthermore, theC-SGN_A 95 acquires the first identification information and/or thethird identification information and/or the fifth identificationinformation and/or the sixth identification information, based on thereception of the ATTACH REQUEST message or the reception of the ESMresponse message.

The C-SGN_A 95 may determine to enter the transmittable and/orreceivable state for the UE_A 10, based on information included in theATTACH REQUEST message, subscriber information, and identificationinformation held by the C-SGN. The transmittable and/or receivable statewhich is a destination of the transition may be determined, based on thefirst identification information, and/or the third identificationinformation, and/or the fifth identification information, and/or thesixth identification information, and/or the subscriber information,and/or the second identification information, and/or the fourthidentification information.

For example, the C-SGN_A 95 approves and determines the transmittableand/or receivable state which is a destination of the transition, basedon the presence or absence of the first identification information,and/or the third identification information, and/or the fifthidentification information, and/or the second identificationinformation, and/or the fourth identification information. In moredetail, the C-SGN_A 95 may approve and determines whether thetransmittable and/or receivable state which is a destination of thetransition is the first mode, the second mode, the third mode or thefourth mode, based on the first identification information, and/or thethird identification information, and/or the fifth identificationinformation, and/or the second identification information, and/or thefourth identification information. Hereinafter, the approval anddetermination process described above is referred to as a firstdetermination and described.

In more detail, the C-SGN_A 95 may enter the transmittable and/orreceivable state in the first mode in a case that the ATTACH REQUESTincludes the first identification information, and the thirdidentification information, and the fifth identification information andthat the C-SGN_A 95 holds the second identification information and doesnot hold the fourth identification information.

Moreover, the C-SGN_A 95 may enter the transmittable and/or receivablestate in the first mode in a case that the ATTACH REQUEST includes thefirst identification information, and that the ATTACH REQUEST does notinclude the third identification information and/or the fifthidentification information, and that the C-SGN_A 95 holds the secondidentification information.

The C-SGN_A 95 may enter the transmittable and/or receivable state inthe second mode in a case that the ATTACH REQUEST includes the firstidentification information, and the third identification information,and the fifth identification information and that the C-SGN_A 95 doesnot hold the second identification information and holds the fourthidentification information.

The C-SGN_A 95 may enter the transmittable and/or receivable state inthe third mode in a case that the ATTACH REQUEST includes the firstidentification information, the third identification information, andthe fifth identification information and that the C-SGN_A 95 holds thesecond identification information and the fourth identificationinformation.

The C-SGN_A 95 may enter the transmittable and/or receivable state inthe fourth mode in a case that the ATTACH REQUEST does not include thefirst identification information.

The C-SGN_A 95 may enter the transmittable and/or receivable state inthe fourth mode in a case that the C-SGN_A 95 does not hold the secondidentification information and the fourth identification information.

Note that the conditions of the transition to the transmittable and/orreceivable state in each mode are not limited above.

In a case of determining to enter the transmittable and/or receivablestate other than the first mode, the C-SGN_A 95 starts an IP-CAN sessionupdate procedure (S2304). The IP-CAN session update procedure may be thesame as the known procedure, and therefore detailed descriptions thereofwill be omitted.

The C-SGN_A 95 may assign an IP address to the UE_A 10 as usual. In moredetail, the C-SGN_A 95 may assign the IP address of the UE_A 10 andinclude the IP address in the seventh identification information.

The C-SGN_A 95 transmits an ATTACH ACCEPT message to the eNB_A 45 withcompletion of the IP-CAN session update procedure (S2306).

Additionally, the C-SGN_A 95 may transmit an Activate default EPS bearercontext request message with the ATTACH ACCEPT message. Hereinafter, inthe description of the present embodiment, the ATTACH ACCEPT message isdescribed as a message in which the ATTACH ACCEPT message and theActivate default EPS bearer context request message are combined.Furthermore, in the description of the present embodiment, in a casethat an expression “identification information is included in the ATTACHACCEPT message” is used, the expression means that the identificationinformation is included in the ATTACH ACCEPT message and/or the Activatedefault EPS bearer context request message.

The C-SGN_A 95 may include at least the second identificationinformation and/or the fourth identification information and/or theseventh identification information in the ATTACH ACCEPT message.

Note that the C-SGN_A 95 may make a connection state for the UE_A 10 theidle mode with the transmission of the ATTACH ACCEPT message based onthe first determination. In other words, the C-SGN_A 95 may make theconnection state for the UE_A 10 the idle mode, based on the transitionto the transmittable and/or receivable state. In more detail, theC-SGN_A 95 may make the connection state for the UE_A 10 the idle mode,based on the transmittable and/or receivable state which is adestination of the transition being the first mode. In other words, in acase of transmitting the ATTACH ACCEPT message for entering thetransmittable and/or receivable state in the second mode, and/or thethird mode, and/or the fourth mode, the C-SGN_A 95 may make theconnection state for the UE_A 10 the active mode with the transmissionof the message.

Note that, in a case that the transmittable and/or receivable statewhich is a destination of the transition is the first mode, the C-SGN_A95 may establish the DRB, and/or the Default Bearer, and/or the PDNconnection for acquisition of the IP address with the UE_A 10 and/or theeNB_A 45, based on the sixth identification information and/or theseventh identification information. In this case, based on theacquisition of the IP address of the UE_A 10, the C-SGN_A 95 may releasethe DRB, and/or the Default Bearer, and/or the PDN connectionestablished with the UE_A 10 and/or the eNB_A 45 for the acquisition ofthe IP address.

The eNB_A 45 receives the ATTACH ACCEPT message, and transmits the RRCmessage including the ATTACH ACCEPT message to the UE_A 10 (S2308). Notethat the RRC message may be an RRC connection reconfiguration requestmessage.

The UE_A 10 receives the RRC message including the ATTACH ACCEPTmessage. Furthermore, in a case that the second identificationinformation and/or the fourth identification information and/or theseventh identification information is included in the ATTACH ACCEPTmessage, the UE_A 10 acquires each piece of identification information.

In order to respond to the received RRC message, the UE_A 10 transmitsthe RRC message to the eNB_A 45 (S2310). The RRC message may be an RRCconnection reconfiguration complete message.

The eNB_A 45 receives an RRC connection reconfiguration message, andtransmits a bearer configuration message to the C-SGN_A 95 based on thereception (S2312).

Additionally, the UE_A 10 transmits the RRC message including an ATTACHCOMPLETE message to the eNB_A 45, based on the reception of the ATTACHACCEPT message (S2314).

Additionally, the UE_A 10 may transmit an Activate default EPS bearercontext accept message with the ATTACH COMPLETE message. Hereinafter, inthe description of the present embodiment, the ATTACH COMPLETE messageis described as a message in which the ATTACH COMPLETE message and theActivate default EPS bearer context accept message are combined.Furthermore, in the description of the present embodiment, in a casethat an expression “identification information is included in the ATTACHCOMPLETE message” is used, the expression means that the identificationinformation is included in the ATTACH COMPLETE message and/or theActivate default EPS bearer context accept message.

Note that the RRC message to be transmitted while including the ATTACHCOMPLETE message may be a Direct Transfer message.

Whether the Activate default EPS bearer context request message is amessage which requires to establish the DRB and/or the Default Bearermay be determined, based on whether the ATTACH ACCEPT message includesthe second identification information and/or the fourth identificationinformation.

In more detail, in a case that the ATTACH ACCEPT includes the secondidentification information and does not include the fourthidentification information, the Activate default EPS bearer contextrequest message may be a message not intended to establish the DRBand/or the Default Bearer.

In other cases, the Activate default EPS bearer context accept messagemay be a message intended to establish the DRB and/or the DefaultBearer.

The UE_A 10 enters the transmittable and/or receivable state, based onthe reception of the ATTACH ACCEPT message and/or the transmission ofthe ATTACH COMPLETE message.

The UE_A 10 may interpret and detect the changed transmittable and/orreceivable state, based on the second identification information and/orthe fourth identification information and/or the seventh identificationinformation. In more detail, the UE_A 10 may interpret and detectwhether the changed transmittable and/or receivable state is the firstmode, the second mode, the third mode, or the fourth mode, based on thesecond identification information, and/or the fourth identificationinformation, and/or the seventh identification information. Hereinafter,the recognition and determination process described above is referred toas a second determination and described.

In more detail, the UE_A 10 may enter the transmittable and/orreceivable state in the first mode in a case that the ATTACH ACCEPTincludes the second identification information and does not include thefourth identification information.

The UE_A 10 may enter the transmittable and/or receivable state in thesecond mode in a case that the ATTACH ACCEPT does not include the secondidentification information and includes the fourth identificationinformation.

The UE_A 10 may enter the transmittable and/or receivable state in thethird mode in a case that the ATTACH ACCEPT includes the secondidentification information and includes the fourth identificationinformation.

The UE_A 10 may enter the transmittable and/or receivable state in thefourth mode in a case that the ATTACH ACCEPT does not include the secondidentification information and does not include the fourthidentification information.

Note that the conditions of the transition to the transmittable and/orreceivable state in each mode are not limited above.

The UE_A 10 may establish the DRB, and/or the Default Bearer, and/or thePDN connection, based on the reception of the ATTACH ACCEPT messageand/or the transmission of the ATTACH COMPLETE message.

Note that in a case that the transmittable and/or receivable state isthe first mode, the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95may not establish the DRB and/or the Default Bearer and/or the PDNconnection.

Even in the case that the transmittable and/or receivable state is thefirst mode, the UE_A 10 and/or the eNB_A 45 and/or the C-SGN_A 95 mayestablish the DRB and/or the Default Bearer and/or the PDN connection ina case that a procedure for acquiring an IP address of the UE_A 10 isrequired based on the sixth identification information and/or theseventh identification information.

The eNB 45 receives the RRC message including the ATTACH COMPLETEmessage, and transmits the ATTACH COMPLETE message to the C-SGN_A 95(S2316).

Additionally, the UE_A 10 may transit to the idle mode with thetransmission of the ATTACH COMPLETE message based on the seconddetermination.

Alternatively, the UE_A 10 may receive the RRC message from the eNB_A 45as the response for the Direct Transfer message including the ATTACHCOMPLETE message, and may transit to the idle mode with the reception ofthe response message based on the second determination.

As a more detailed example, the UE_A 10 may transmit identificationinformation indicating the transition to the idle mode included in theATTACH COMPLETE message and/or the Direct Transfer message.

Furthermore, the eNB_A 45 which receives the Direct Transfer message maytransmit the RRC message to be a response to the UE_A 10 based on thereceived identification information. As described above, the RRC messageto be the response may be a message for allowing the transition to theidle mode.

In other words, the UE_A 10 can select whether to transit to the idlemode or to maintain the active mode based on the second determination.

Alternatively, in a case that the changed transmittable and/orreceivable state is the first mode, the UE_A 10 may establish aconnection for IP address acquisition with the eNB_A 45 and/or theC-SGN_A 95, based on the sixth identification information and/or theseventh identification information. Note that the connection may be theDRB, and/or the Default Bearer, and/or the PDN connection.

For example, in a case that the changed transmittable and/or receivablestate is the first mode, and the seventh identification informationindicates that acquisition of the IP address is required aftercompletion of the attach procedure, the UE_A 10 may establish aconnection for IP address acquisition with the eNB_A 45 and/or theC-SGN_A 95.

In more detail, in a case that the established transmittable and/orreceivable is the first mode, and the seventh identification informationincludes an IPv4 address with all elements indicated by zero such as0.0.0.0, and/or any interface ID of the IPv6, the UE_A 10 may establishthe connection for IP address acquisition.

Note that in a case that the IPv4 address field of the seventhidentification information includes an IPv4 address with all elementsindicated by zero such as 0.0.0.0, the UE_A 10 may initiate a DHCPprocedure to acquire an IPv4 address.

Specifically, the UE_A 10 may transmit a message which requests an IPv4address from a DHCP server, based on the above-described conditions. TheUE_A 10 may acquire the IPv4 address by receiving a response messageincluding an IPv4 address assigned to the UE_A 10 from the DHCP server.

In a case that the IPv6 address field of the seventh identificationinformation includes any interface ID of the IPv6, the UE_A 10 mayacquire the IPv6 prefix indicated by upper 64 bit information of theIPv6 address, and creates or acquires the IPv6 address by using thestateless address configuration procedure.

Specifically, the UE_A 10 may transmit a Router Solicitation (RS)message which requests the IPv6 prefix from a router and/or a server,based on the above-described conditions. The UE_A 10 may acquire theIPv6 prefix by receiving a Router Advertisement (RA) message includingthe assigned IPv6 prefix from the router and/or the server. Furthermore,the UE_A 10 may create or acquire the IPv6 from the acquired IPv6 prefixand the interface ID of the IPv6, based on the reception of the RAmessage, and/or the reception of the IPv6 prefix included in the RAmessage.

For example, in a case that the changed transmittable and/or receivablestate is the first mode, and the sixth identification informationindicates an IPv4 address, and the seventh identification includes anIPv4 address used by the UE_A 10, the IPv4 address not being an IPv4address with all elements indicated by zero such as 0.0.0.0, and theseventh identification does not include an IPv6 interface ID, the UE_A10 may not establish the connection for IP address acquisition.

Moreover, in a case that the changed transmittable and/or receivablestate is the first mode, and the connection for IP address acquisitionis established, the UE_A 10 may release the connection established withthe eNB_A 45 and/or the C-SGN_A 95, based on the acquisition of IPaddress.

Hereinafter, a UE_A 10 initiated procedure for releasing the connectionbetween the UE_A 10, and the eNB_A 45 and/or the C-SGN_A 95 will bedescribed.

The UE_A 10 transmits a connection release request message to the eNB_A45 and/or the C-SGN_A 95. The connection release request message may bea message for requesting the release of the connection.

The eNB_A 45 receives the connection release request message transmittedby the UE_A 10. The eNB_A 45, based on the reception of the connectionrelease request message, transmits a connection release request messageto the C-SGN_A 95.

The C-SGN_A 95 receives the connection release request messagetransmitted by the eNB_A 45 and/or the UE_A 10. The C-SGN_A 95, based onthe reception of the connection release request message, transmits aconnection release accept message to the eNB_A 45 and/or the UE_A 10,Here, the connection release accept message may be a response message tothe connection release request message.

The C-SGN_A 95, based on the reception of the connection release requestmessage and/or the transmission of the connection release acceptmessage, releases the context of the C-SGN_A 95 for the connection, Thecontext of the C-SGN_A 95 for the connection may be the context D and/orthe context E illustrated in FIG. 19(a).

The eNB_A 45 receives the connection release accept message transmittedby the C-SGN_A 95. The eNB_A 45, based on the reception of theconnection release accept message, transmits a connection release acceptmessage to the UE_A 10.

The eNB_A 45, based on the reception of the connection release requestmessage, and/or the reception of the connection release accept message,and/or the transmission of the connection release accept message,releases the context of the eNB_A 45 for the connection,

The UE_A 10 receives the connection release accept message transmittedby the eNB_A 45 and/or the C-SGN_A 95.

The UE_A 10, based on the transmission of the connection release requestmessage and/or the reception of the connection release accept message,releases the context of the UE_A 10 for the connection, The context ofthe UE_A 10 for the connection may be a UE context stored in thetransmittable and/or receivable state illustrated in FIG. 21(c) and/or aUE context for each bearer illustrated in FIG. 21(d).

By the above-described procedures, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 releases the context for the connection, and theconnection between the UE_A 10, and the eNB_A 45 and/or the C-SGN_A 95is released.

The C-SGN_A 95 receives the ATTACH COMPLETE message.

The C-SGN_A 95 may transit the connection state for the UE_A 10 to theidle mode based on the reception of the ATTACH COMPLETE message.

In other words, the C-SGN_A 95 may manage the state of the UE_A 10 asthe idle mode based on the transmission of the ATTACH ACCEPT message orthe reception of the ATTACH COMPLETE message.

In more detail, in a case that the transmittable and/or receivable statewhich is the transition destination is the second mode and/or the thirdmode and/or the fourth mode, the C-SGN_A 95 may manage the state of theUE_A 10 as the idle mode based on the transmission of the ATTACH ACCEPTmessage or the reception of the ATTACH COMPLETE message.

Note that the UE_A 10 can acquire the UE context illustrated in FIG. 21from the core network_A 90 by the attach procedure and store thecontext.

Additionally, the C-SGN_A 95 can acquire each of the contexts A to Eillustrated in FIG. 19(a) from the UE_A 10, the eNB_A 45, or the HSS_A50 by the attach procedure and store the contexts.

By the above-described steps, the UE_A 10 connects to the network, andcompletes the first attach procedure. Note that the UE_A 10 and/or theC-SGN_A 95 enter the transmittable and/or receivable state with thecompletion of the first attach procedure.

1.3.1.2. Second Attach Procedure Example

Hereinafter, an example of the steps of a second attach procedure willbe described using FIG. 24.

Note that the steps from the transmission of an ATTACH REQUEST messageby the UE_A 10 to the reception of the ATTACH REQUEST message by theC-SGN_A 95 may be the same as the steps in the procedure of (A) in FIG.23 (S2400). Therefore, description of the steps will be omitted.

The C-SGN_A 95 receives the ATTACH REQUEST message. Furthermore, theC-SGN_A 95 acquires the first identification information and/or thethird identification information and/or the fifth identificationinformation and/or the sixth identification information, based on thereception of the ATTACH REQUEST message or the reception of the ESMresponse message.

The C-SGN_A 95 may determine not to enter the transmittable and/orreceivable state for the UE_A 10, based on information included in theATTACH REQUEST message and the subscriber information. The C-SGN_A 95may determine not to enter the transmittable and/or receivable state,based on the first identification information, and/or the thirdidentification information, and/or the fifth identification information,and/or the sixth identification information, and/or the subscriberinformation. Hereinafter, the determination process described above isreferred to as a thirteenth determination and described.

The C-SGN_A 95 transmits an ATTACH REJECT message to the eNB_A 45, basedon the thirteenth determination (S2402). The C-SGN_A 95 may transmit aPDN connectivity reject message with the ATTACH REJECT message.Hereinafter, in the description of the present embodiment, the ATTACHREJECT message is described as a message in which the ATTACH REJECTmessage and the PDN connectivity reject message are combined.Furthermore, in the description of the present embodiment, in a casethat an expression “identification information is included in the ATTACHREJECT message” is used, the expression means that the identificationinformation is included in the ATTACH REJECT message and/or the PDNconnectivity reject message.

The C-SGN_A 95 may include at least the second identificationinformation and/or the eighth identification information in the ATTACHREJECT message.

The eNB_A 45 receives the ATTACH REJECT message, and transmits the RRCmessage including the ATTACH REJECT message to the UE_A 10 (S2208). Notethat the RRC message may be an RRC connection reconfiguration requestmessage.

The UE_A 10 receives the RRC message including the ATTACH REJECTmessage. The UE_A 10 may detect failure of transition to thetransmittable and/or receivable state, based on the reception of theATTACH REJECT message, and/or the second identification informationand/or the eighth identification information included in the ATTACHREJECT message.

By the above-described steps, the UE_A 10 fails to connect to thenetwork, and completes the second attach procedure.

The UE_A 10 may perform a new attach procedure, based on the failure ofconnecting to the network. In more detail, the UE_A 10 may perform thenew attach procedure, based on the second identification informationand/or the eighth identification information included in the ATTACHREJECT message.

1.3.1.3. Third Attach Procedure Example

Hereinafter, an example of the steps of a third attach procedure will bedescribed using FIG. 25.

Note that the steps from the transmission of an ATTACH REQUEST messageto the reception of the ATTACH ACCEPT message by the UE_A 10 may be thesame as the steps in the procedures of (A) and (B) in FIG. 23 (S2500,S2502). Therefore, description of the steps will be omitted.

The UE_A 10 receives the RRC message including the ATTACH ACCEPTmessage. Furthermore, in a case that the second identificationinformation and/or the fourth identification information and/or theseventh identification information is included in the ATTACH ACCEPTmessage, the UE_A 10 acquires each piece of identification information.

The UE_A 10 may interpret and detect the transmittable and/or receivablestate allowed by the C-SGN_A 95, based on the second identificationinformation and/or the fourth identification information and/or theseventh identification information. In more detail, the UE_A 10 mayinterpret and detect whether the transmittable and/or receivable stateallowed by the C-SGN_A 95 is the first mode, the second mode, the thirdmode, or the fourth mode, based on the second identificationinformation, and/or the fourth identification information, and/or theseventh identification information.

Furthermore, the UE_A 10 may determine to reject the transition to thetransmittable and/or receivable state, based on the authentication anddetection of the transmittable and/or receivable state allowed by theC-SGN_A 95. In more detail, in a case that a transmittable and/orreceivable state different from a mode intended by the UE_A 10 isallowed by the C-SGN_A 95, the UE_A 10 may determine to reject thetransition to the transmittable and/or receivable state. Hereinafter,the interpretation and determination process described above is referredto as a fourteenth determination and described.

In a case that the UE_A 10 determines to reject the transition to thetransmittable and/or receivable state by the fourteenth determination,the UE_A 10 transmits an Activate default EPS bearer context rejectmessage to the C-SGN_A 95 via the eNB_A 45 (S2504).

The UE_A 10 may include at least the ninth identification information inthe Activate default EPS bearer context reject message. The UE_A 10 mayreject the transition to the transmittable and/or receivable state bytransmitting the ATTACH REQUEST message including the ninthidentification information.

The C-SGN_A 95 receives the Activate default EPS bearer context rejectmessage. The C-SGN_A 95 may detect failure of transition to thetransmittable and/or receivable state, based on the received Activatedefault EPS bearer context reject message, and/or the ninthidentification information included in the Activate default EPS bearercontext reject message.

In more detail, the C-SGN_A 95 may release the context for the UE_A 10illustrated in FIG. 19(a), based on the received Activate default EPSbearer context reject message, and/or the ninth identificationinformation included in the Activate default EPS bearer context rejectmessage.

By the above-described steps, the UE_A 10 fails to connect to thenetwork, and completes the third attach procedure.

The UE_A 10 may perform a new attach procedure, based on the failure ofconnecting to the network. In more detail, the UE_A 10 may perform thenew attach procedure, based on the second identification informationand/or the eighth identification information included in the ATTACHREJECT message.

1.3.1.4. Modified Example of Attach Procedure

Note that although the attach procedure is described in a case that thecore network_A 90 in the attach procedure example described above is acore network configured by including the C-SGN_A 95 described using FIG.3(a), the core network_A 90 may be a core network configured byincluding the PGW_A 30, the SGW_A 35, the MME_A 40, or the like asdescribed using FIG. 2.

In this case, the NAS message such as the ATTACH REQUEST message, theATTACH COMPLETE message, or the like transmitted by the UE_A 10described in this procedure is received by the MME 45, not by theC-SGN_A 95.

Accordingly, the reception and the processes of the NAS message by theC-SGN_A 95 in the above description can be replaced with those performedby the MME_A 40.

Furthermore, the transmission and the processes of the NAS message suchas the ATTACH ACCEPT message or the like by the C-SGN_A 95 in the abovedescription can be replaced with those performed by the MME_A 40.

1.3.2. Selection Example of Transmission and/or Reception Means

Next, a method of selecting a transmission and/or reception procedure tobe used at the time of transmitting the UL user data by the UE_A 10which entered to the transmittable and/or receivable state will bedescribed.

The UE_A 10 selects and determines a procedure to be used to transmitthe UL user data among the first transmission and/or receptionprocedure, the second transmission and/or reception procedure, and thethird transmission and/or reception procedure.

Here, the first transmission and/or reception procedure may be aprocedure for performing transmission and/or reception withconnectionless, and the second transmission and/or reception procedureand/or the third transmission and/or reception procedure may be aprocedure for establishing a connection to perform transmission and/orreception. The third transmission and/or reception procedure may be aknown transmission and/or reception procedure.

The UE_A 10 may detect and determine these, based on the transmittableand/or receivable state which is the transition destination. In otherwords, the UE_A 10 may select and determine these, based on the mode ofthe transmittable and/or receivable state determined in the seconddetermination. The UE_A 10 may detect and determine these, based on thedata size of the transmitted UL user data.

In more detail, the UE_A 10 may select and determine to use the firsttransmission and/or reception procedure, based on the transmittableand/or receivable state being the first mode and/or the third mode.

Moreover, the UE_A 10 may select and determine to use the secondtransmission and/or reception procedure, based on the transmittableand/or receivable state being the second mode and/or the third mode.

Furthermore, the UE_A 10 may select and determine to use the thirdtransmission and/or reception procedure, based on the transmittableand/or receivable state being the fourth mode.

Furthermore, the UE_A 10 may select and determine to use the secondtransmission and/or reception procedure and/or the third transmissionand/or reception procedure, based on UL user data of large data size tobe transmitted. Note that the large data size may indicate that the datasize is larger than a threshold.

The UE_A 10 may branch into the first transmission and/or receptionprocedure, the second transmission and/or reception procedure, and thethird transmission and/or reception, regardless of these conditions.

Hereinafter, selection and determination of a procedure to be used totransmit the UL user data among the first transmission and/or receptionprocedure, the second transmission and/or reception procedure, and thethird transmission and/or reception procedure are referred to as a thirddetermination and described.

1.3.3. UL User Data Transmission and/or Reception Procedure Example

Next, steps in which the UE_A 10 having established the connection tothe network transmits the UL user data will be described.

Hereinafter, transmission steps of the UL user data will be described.

The UE_A 10 transmits a first message to the eNB_A 45. The first messageis a message for requesting at least transmission timing information andresource assignment information, and the UE_A 10 transmits the firstmessage at least including a randomly selected preamble to the eNB_A 45.

Note that the first message is a control signal of a Physical layer, maybe a Random Access Channel (RACH) Preamble message of Message 1. Thefirst message may be transmitted using a Physical Random Access Channel(PRACH).

The eNB_A 45 receives the first message, and transmits a second messageto the UE_A 10 as a response to the first message. The second message istransmitted while including at least the transmission timing informationand the resource assignment information. To be more specific, thetransmission timing information may be a Timing Advance, and theresource assignment information may be a UL Grant. The second message isa control signal in a Media Access Control (MAC) layer, and may betransmitted using a Medium Access Control Random Access Response (MACRAR).

Note that the second message may be a RACH Response message of Message2.

A communication procedure after the UE_A 10 receives the second messagecan branch into a first transmission and/or reception procedure example,a second transmission and/or reception procedure example, and a thirdtransmission and/or reception example, which will be described later.

The UE_A 10 may branch into the first transmission and/or receptionprocedure example, and/or the second transmission and/or receptionprocedure example, and/or the third transmission and/or receptionexample, based on the third determination.

1.3.3.1. Description of First Transmission and/or Reception ProcedureExample

The first transmission and/or reception procedure example is a procedurein which the UE_A 10 transmits and/or receives the user data withoutestablishing any Data Radio Bearer (DRB). In other words, the firsttransmission and/or reception procedure example is a procedure fortransmitting the user data by using a radio bearer for transmittingand/or receiving a control message.

Hereinafter, the first transmission and/or reception procedure examplewill be described in detail using FIG. 26.

The UE_A 10 transmits, based on the reception of the second message fromthe eNB_A 45, the third message to the eNB_A 45 (S2600).

The eNB_A 45 receives the third message transmitted by the UE_A 10. Onthe basis of the reception of the third message, the eNB_A 45 transmitsa fourth message to the UE_A 10 (S2602).

The UE_A 10 transmits the fourth message transmitted by the eNB_A 45. Onthe basis of the reception of the fourth message, the UE_A 10 transmitsa fifth message to the eNB_A 45 (S2604).

The UE_A 10 may transmit the NAS message including the UL user datawhile being included in the third message and/or the fifth message. Notethat the UE_A 10 may encrypt the UL user data or the NAS messageincluding the UL user data to transmit the encrypted UL user data or NASmessage.

The eNB_A 45 receives the NAS message including the UL user data, basedon the reception of the third message and/or the fifth message.

On the basis of the reception of the NAS message including the UL userdata, the eNB_A 45 may transmit an Initial UE message of an S1Application Protocol (S1AP) to the C-SGN_A 95 (S2606).

The eNB_A 45 may transmit the S1AP Initial UE message including at leastthe NAS message in which the UL user data is included.

The eNB_A 45 may transmit a complete message to the UE_A 10, based onthe reception of the third message and/or the fifth message, and/or thetransmission of the S1AP Initial UE message (S2608).

The UE_A 10 receives the complete message transmitted by the eNB_A 45.

The C-SGN_A 95 receives the S1AP Initial UE message transmitted by theeNB_A 45, and/or the NAS message including the UL user data included inthe S1AP Initial UE message

On the basis of the reception of the NAS message including the UL userdata included in the S1AP Initial UE message, the C-SGN_A 95 decryptsthe received NAS message and/or extracts the user data included in thereceived NAS message (S2610). Note that the C-SGN_A 95 may decrypt theextracted user data, as needed.

The C-SGN_A 95 transmits the user data to the PDN_A 5, based on theextraction and/or decryption of the user data included in the NASmessage (S2612). The C-SGN_A 95 may transmit to the PDN_A 5 afterdecrypting the user data.

By the above-described procedures, the UE_A 10 can transmit the smalldata packet being the UL user data to the PDN_A 5 without establishingthe Data Radio Bearer (DRB). Furthermore, after the completion of thefirst transmission and/or reception procedure example, the UE_A 10 canenter the idle state, or maintain the idle state.

Note that, in a case that the user data to be transmitted and/orreceived has a large size, the UE_A 10 and/or the C-SGN_A 95 do nottransmit and/or receive the user data through the first transmissionand/or reception procedure, and may transmit the user data through thesecond transmission and/or reception procedure.

1.3.3.2. Description of Second Transmission and/or Reception ProcedureExample

The second transmission and/or reception procedure example is aprocedure in which the UE_A 10 transmits and/or receives the user dataafter establishing a DRB.

Hereinafter, the second transmission and/or reception procedure examplewill be described in detail using FIG. 27.

The UE_A 10 transmits, based on the reception of the second message fromthe eNB_A 45, the third message to the eNB_A 45 (S2700).

The UE_A 10 may transmit at least the NAS message and/or the Resume IDwhile being included in the third message.

Note that the NAS message may be a message for re-establishing a DRB.

The Resume ID may be identification information for identifying the DRBto be re-established. Additionally/Alternatively, the Resume ID may beidentification information for identifying the context held by the eNB_A45, the context being associated with the DRB to be re-established.Additionally/Alternatively, the Resume ID may be identificationinformation for indicating to make the CIoT terminal in the active stateenter the idle state. Additionally/Alternatively, the Resume ID may beidentification information for indicating to make the CIoT terminal inthe idle state enter the active state.

For example, the eNB_A 45 may enter the idle state from the active stateby transmitting the Resume ID to the UE_A 10. Moreover, the UE_A 10 mayenter the idle state from the active state by receiving the Resume IDfrom the eNB_A 45.

The UE_A 10 may enter the active state from the idle state bytransmitting the received Resume ID to the eNB_A 45. Moreover, the eNB_A45 may enter the active state from the idle state by receiving theResume ID from the UE_A 10.

Note that the context used in the previous active state can beidentified by using the same Resume ID for the Resume ID transmittedand/or received for the transition from the active state to the idlestate and the Resume ID transmitted and/or received for the transitionfrom the idle state to the active state. The UE_A 10 and the eNB_A 45can re-establish a DRB, based on the identified context, or the like, torestore a communication state similar to the last active state.

In this way, each of the UE_A 10 and the eNB_A 45 can change its statebetween the active state and the idle state, based on the Resume ID. TheeNB_A 45 receives the third message transmitted by the UE_A 10. TheeNB_A 45 receives the NAS message and/or the Resume ID, based on thereception of the third message.

On the basis of the reception of the resume ID included in the thirdmessage, the eNB_A 45 re-establishes the DRB identified by the resumeID.

The eNB_A 45 transmits a fourth message to the UE_A 10, based on thereception of the third message and/or the re-establishment of the DRBidentified by the Resume ID (S2702).

The eNB_A 45 may transmit at least the Resume ID for identifying there-established DRB while being included in the fourth message.

The eNB_A 45 changes the state of the eNB_A 45 into the active mode,based on the reception of the third message, and/or the reception of theNAS message, and/or the re-establishment of the DRB identified by theResume ID, and/or the transmission of the fourth message.

The eNB_A 45 transmits an S1 Application Protocol (S1AP) UE ContextActive message to the C-SGN_A 95, based on the reception of the thirdmessage, and/or the reception of the NAS message, and/or there-establishment of the DRB identified by the Resume ID, and/or thetransmission of the fourth message, and/or the state transition of theeNB_A 45 to the active mode (S2704). The eNB_A 45 may transmit the S1APUE Context Active message including the NAS message.

The C-SGN_A 95 receives the S1AP UE Context Active message. On the basisof the reception of the S1AP UE Context Active message, the C-SGN_A 95changes the state of the C-SGN_A 95 into the active mode. On the basisof the reception of the S1AP UE Context Active message, and/or thereception of the NAS message, and/or the state transition of the C-SGN_A95 to the active mode, the C-SGN_A 95 transmits an S1AP UE contextactive response message to the eNB_A 45 (S2706).

The UE_A 10 receives the fourth message transmitted by the eNB_A 45. TheUE_A 10 changes the state of the UE_A 10 to the active mode, based onthe reception of the fourth message and/or the reception of the ResumeID for identifying the re-established DRB included in the fourthmessage.

The UE_A 10 transmits the UL user data to the PDN_A 5 via the eNB_A 45and/or the C-SGN_A 95, based on the reception of the fourth message,and/or the reception of the Resume ID for identifying the re-establishedDRB included in the fourth message, and/or the state transition of theUE_A 10 to the active mode (S2708) (S2710) (S2712).

The UE_A 10 continues transmitting the UL user data to the PDN_A 5 viathe eNB_A 45 and/or the C-SGN_A 95, as long as the UL user data to betransmitted exists. Note that presence or absence of the data to betransmitted may be determined from a data residual amount of the bufferwhich accumulates the UL user data to be transmitted or the like.

By the above-described procedures, the UE_A 10 can transmit the UL userdata. Furthermore, the UE_A 10 can also receive DownLink (DL) user databy the above-described procedures. Note that the DL user data istransmitted from the PDN_A 5, and can be received through the C-SGN_A 95and the eNB_A 45.

The eNB_A 45 transfers the UL user data received from the UE_A 10 to theC-SGN_A 95.

In a case of detecting no reception of the UL user data for a certainperiod of time, the eNB_A 45 starts the procedure for changing thestate(s) of the UE_A 10, and/or the eNB_A 45, and/or the C-SGN_A 95 tothe idle mode, as illustrated in FIG. 5. In other word, the eNB_A 45does not perform a procedure like the procedure (A) in FIG. 27, as longas the eNB_A 45 continues receiving the UL user data.

The eNB_A 45 transmits the S1AP UE context release message to theC-SGN_A 95, based on the detection of no reception of the UL user datafor a certain period of time (S2714).

The C-SGN_A 95 receives the S1AP UE context release message. On thebasis of the reception of the S1AP UE context release message, theC-SGN_A 95 changes the state of the C-SGN_A 95 into the idle mode. Onthe basis of the reception of the S1AP UE context release message,and/or the state transition of the C-SGN_A 95 to the idle mode, theC-SGN_A 95 transmits an S1AP UE context release response message to theeNB_A 45 (S2716).

The eNB_A 45 transmits an RRC Connection Suspend message to the UE_A 10,based on the transmission of the UE context release message, and/orreception of the UE context release response (S2718).

The eNB_A 45 may transmit at least the Resume ID while being included inthe RRC Connection Suspend message.

Here, the Resume ID may be identification information for identifyingthe DRB to be released. In more detail, the Resume ID may beidentification information for identifying the context held by the UE_A10 and/or the eNB_A 45, the context being associated with the DRB to bereleased.

On the basis of the transmission of the RRC Connection Suspend messagethe Resume ID, the eNB_A 45 releases the DRB identified by the ResumeID. Note that the eNB_A 45 releases the DRB identified by the Resume ID,but may continue to hold the context associated with the released DRBwithout deleting the context.

The eNB_A 45 changes the state of the eNB_A 45 into the idle mode, basedon the release of the DRB identified by the Resume ID.

The UE_A 10 receives the RRC Connection Suspend message transmitted bythe eNB_A 45.

On the basis of the reception of the RRC Connection Suspend message,and/or the reception of the Resume ID included in the RRC ConnectionSuspend message, the UE_A 10 releases the DRB identified by the ResumeID. Note that the UE_A 10 releases the DRB identified by the Resume ID,but may continue to hold the context associated with the released DRBwithout deleting the context.

The UE_A 10 changes the state of the UE_A 10 into the idle mode, basedon the release of the DRB identified by the Resume ID.

By the above-described procedures, the UE_A 10 and/or the eNB_A 45and/or the C-SGN_A 95 can release the DRB and enter the idle mode whileholding the context for the UE_A 10 and/or the eNB_A 45

1.3.3.3. Description of Third Transmission and/or Reception ProcedureExample

The third transmission and/or reception procedure example is a knowntransmission and/or reception procedure.

The third transmission and/or reception procedure example is a procedurein which the UE_A 10 transmits and/or receives the user data afterestablishing a DRB.

The third transmission and/or reception procedure may be a similarprocedure to the second transmission and/or reception procedure.Therefore, detailed description of the procedure will be omitted.

In a case of the third procedure, the UE_A 10 may not include the NASmessage and/or the Resume ID in the third message, and may transmit theNAS message while being included in the fifth message.

Furthermore, the S1AP message(s) transmitted and/or received between theeNB_A 45 and the C-SGN_A 95 is not limited to the UE Context Activemessage and/or the UE context active response message, and may be anymessage transmitting and/or receiving the NAS message.

Moreover, the UE_A 10 may transmit the UL user data, based on thereception of a response message to the fifth message.

1.3.3.4. Modified Example of UL User Data Transmission and/or ReceptionProcedure

Note that although the attach procedure is described in a case that thecore network_A 90 in the UL user data transmission and/or receptionprocedure example described above is a core network configured byincluding the C-SGN_A 95 described using FIG. 3(a), the core network_A90 may be a core network configured by including the PGW_A 30, the SGW_A35, the MME_A 40, or the like as described using FIG. 2.

In this case, the NAS message transmitted by the UE_A 10 described inthis procedure is received by the MME 45, not by the C-SGN_A 95.

Accordingly, the reception and the processes of the NAS message by theC-SGN_A 95 in the above description can be replaced with those performedby the MME_A 40.

Furthermore, the transmission and the processes of the NAS message bythe C-SGN_A 95 in the above description can be replaced with thoseperformed by the MME_A

1.3.4. Detach Procedure Example

Next, an example of a detach procedure will be described. Note that thedetach procedure is a procedure which is started on the initiative ofthe UE_A 10 and/or the C-SGN_A 95 and/or the HSS_A 50, and a procedurefor disconnecting the connection to the network. A trigger for startingthe detach procedure by the UE_A 10, and/or the C-SGN_A 95, and/or theHSS_A 50 may be deterioration of a radio wave state of a 3GPP accesssystem, detection of unstable connectivity, or the like.

Additionally, the UE_A 10 may start at an arbitrary timing in a casethat the UE_A 10 is connected to the core network_A 90 regardless of theabove. The C-SGN_A 95 and/or the HSS_A 50 may start at an arbitrarytiming.

Note that the details of the detach procedure may be a procedure to bedescribed as the UE initiated detach procedure example, and may be aprocedure to be described as the network initiated detach procedureexample.

1.3.4.1. Description of UE Initiated Detach Procedure Example

This procedure is a procedure initiated by the UE_A 10, in which aconnection of the UE_A 10 to the network is disconnected.

Hereinafter, an example of the steps of the UE initiated detachprocedure will be described using FIG. 28.

First, the UE_A 10 transmits a DETACH REQUEST message to the C-SGN_A 95(S2800). Note that the UE_A 10 may transmit the DETACH REQUEST messageto the eNB_A 45, and the transmitted DETACH REQUEST message may betransferred to the C-SGN_A 95 via the eNB 45.

The UE_A 10 may include at least the tenth identification information inthe DETACH REQUEST message. The UE_A 10 may request disconnection of theconnection to the network, by transmitting the DETACH REQUEST messageincluding the tenth identification information.

The C-SGN_A 95 receives the DETACH REQUEST message. Furthermore, theC-SGN_A 95 acquires the tenth identification information, based on thereception of the DETACH REQUEST message.

On the basis of the reception of the DETACH REQUEST, and/or the tenthidentification information included in the DETACH REQUEST, the C-SGN_A95 may start the IP-CAN session termination procedure (S2802). TheIP-CAN session termination procedure may be the same as the knownprocedure, and therefore detailed descriptions thereof will be omitted.

The C-SGN_A 95 transmits a DETACH ACCEPT message to the UE_A 10 via theeNB_A 45 with completion of the IP-CAN session termination procedure(S2804). Note that the DETACH ACCEPT message may be a response messageto the DETACH REQUEST message.

On the basis of the reception of the DETACH REQUEST, and/or completionof the IP-CAN session termination procedure, and/or transmission of theDETACH ACCEPT, and/or the tenth identification information included inthe DETACH REQUEST, the C-SGN_A 95 may disconnect the connection to thenetwork. In more detail, the C-SGN_A 95 may release the context used forthe connection to the network, and thus disconnect the connection to thenetwork.

Note that the context used for the connection to the network to bedeleted may be the context A, and/or the context B, and/or the contextC, and/or the context D, and/or the context E, which are illustrated inFIG. 19 (a).

The UE_A 10 receives the DETACH ACCEPT transmitted by the C-SGN_A 95.

The UE_A 10 may disconnect the connection to the network, based on thereception of the DETACH ACCEPT. In more detail, the UE_A 10 may releasethe context used for the connection to the network, and thus disconnectthe connection to the network.

Note that the context used for the connection to the network to bereleased may be the UE context stored in the transmittable and/orreceivable state illustrated in FIG. 21(c), and/or the UE context foreach bearer illustrated in FIG. 21(d).

Furthermore, the UE_A 10 may perform a signalling connection releaseprocedure with the eNB_A 45, based on the reception of the DETACHACCEPT. In other words, the eNB_A 45 may perform the signallingconnection release procedure with the UE_A 10, based on the transmissionof the DETACH ACCEPT.

By the above-described steps, the UE_A 10 and/or the C-SGN_A 95disconnect the connection to the network and complete the detachprocedure.

Note that although the detach procedure is described in a case that thecore network_A 90 in the detach procedure example described above is acore network configured by including the C-SGN_A 95 described using FIG.3(a), the core network_A 90 may be a core network configured byincluding the PGW_A 30, the SGW_A 35, the MME_A 40, or the like asdescribed using FIG. 2.

In this case, the NAS message such as the DETACH REQUEST message or thelike transmitted by the UE_A 10 described in this procedure is receivedby the MME 45, not by the C-SGN_A 95.

Accordingly, the reception and the processes of the NAS message by theC-SGN_A 95 in the above description can be replaced with those performedby the MME_A

Furthermore, the transmission and the processes of the NAS message suchas the DETACH ACCEPT message or the like by the C-SGN_A 95 in the abovedescription can be replaced with those performed by the MME_A 40.

1.3.4.2. Description of Network Initiated Detach Procedure Example

This procedure is a procedure initiated by the C-SGN_A 95 and/or theHSS_A 50, in which a connection of the UE_A 10 to the network isdisconnected.

Hereinafter, an example of the steps of the network initiated detachprocedure will be described using FIG. 5.

First, the HSS_A 50 transmits a Cancel Location message to the C-SGN_A95 (S2900). The HSS_A 50 may include the twelfth identificationinformation in the Cancel Location message.

The C-SGN_A 95 receives the Cancel Location message. The C-SGN_A 95transmits a DETACH REQUEST message to the UE_A 10 via the eNB_A 45,based on the Cancel Location message and/or the twelfth identificationinformation included in the Cancel Location message (S2902).

Moreover, the C-SGN_A 95 may transmit the DETACH REQUEST message to theUE_A 10 via the eNB_A 45 at an arbitrary timing, not based on thereception of the Cancel Location message.

The C-SGN_A 95 may include at least the eleventh identificationinformation and/or the twelfth identification information in the DETACHREQUEST message. The C-SGN_A 95 may request disconnection of theconnection to the network, by transmitting the DETACH REQUEST messageincluding the eleventh identification information and/or the twelfthidentification information.

The C-SGN_A 95 transmits a Cancel Location ACK message to the HSS_A 50,based on the reception of the Cancel Location message, and/or thereception of the eleventh identification information included in theCancel Location message, and/or the transmission of the DETACH REQUESTmessage (S2904). Note that the Cancel Location ACK message may be aresponse message to the Cancel Location message.

The C-SGN_A 95 may start the IP-CAN session termination procedure, basedon the reception of the Cancel Location message, and/or the reception ofthe eleventh identification information included in the Cancel Locationmessage, and/or the transmission of the DETACH REQUEST message, and/orthe transmission of the Cancel Location ACK message (S2906). The IP-CANsession termination procedure may be the same as the known procedure,and therefore detailed descriptions thereof will be omitted.

The UE_A 10 receives the DETACH REQUEST message transmitted by theC-SGN_A 95. Furthermore, the UE_A 10 acquires the eleventhidentification information and/or the twelfth identificationinformation, based on the reception of the DETACH REQUEST message.

The UE_A 10 transmits a DETACH ACCEPT message to the C-SGN_A 95 via theeNB_A 45, based on the reception of the DETACH REQUEST message, and/orthe eleventh identification information and/or the twelfthidentification information included in the DETACH REQUEST message(S2908). Note that the DETACH ACCEPT message may be a response messageto the DETACH REQUEST message.

On the basis of the reception of the DETACH REQUEST, and/or transmissionof the DETACH ACCEPT, and/or the eleventh identification informationand/or the twelfth identification information included in the DETACHREQUEST, the UE_A 10 may disconnect the connection to the network. Inmore detail, the UE_A 10 may release the context used for the connectionto the network, and thus disconnect the connection to the network.

Note that the context used for the connection to the network to bereleased may b e the UE context stored in the transmittable and/orreceivable state illustrated in FIG. 21(c), and/or the UE context foreach bearer illustrated in FIG. 21(d).

The C-SGN_A 95 receives the DETACH ACCEPT transmitted by the UE_A 10.

The C-SGN_A 95 receives the DETACH ACCEPT. Additionally/Alternatively,the C-SGN_A 95 may disconnect the connection to the network, based onthe completion of the IP-CAN session termination procedure, and/or thetransmission of the Cancel Location ACK message. In more detail, theC-SGN_A 95 may release the context used for the connection to thenetwork, and thus disconnect the connection to the network.

Note that the context used for the connection to the network to bedeleted may be the context A, and/or the context B, and/or the contextC, and/or the context D, and/or the context E, which are illustrated inFIG. 19 (a).

Furthermore, the UE_A 10 may perform the signalling connection releaseprocedure with the eNB_A 45, based on the transmission of the DETACHACCEPT. In other words, the eNB_A 45 may perform the signallingconnection release procedure with the UE_A 10, based on the reception ofthe DETACH ACCEPT.

By the above-described steps, the UE_A 10 and/or the C-SGN_A 95disconnect the connection to the network and complete the detachprocedure.

1.3.4.3. Modified Example of Detach Procedure

Note that although the detach procedure is described in a case that thecore network_A 90 in the detach procedure example described above is acore network configured by including the C-SGN_A 95 described using FIG.3(a), the core network_A 90 may be a core network configured byincluding the PGW_A 30, the SGW_A 35, the MME_A 40, or the like asdescribed using FIG. 2.

In this case, the NAS message such as the DETACH REQUEST message or thelike transmitted by the UE_A 10 described in this procedure is receivedby the MME 45, not by the C-SGN_A 95.

Accordingly, the reception and the processes of the NAS message by theC-SGN_A 95 in the above description can be replaced with those performedby the MME_A

Furthermore, the transmission and the processes of the NAS message suchas the DETACH ACCEPT message or the like by the C-SGN_A 95 in the abovedescription can be replaced with those performed by the MME_A 40.

2. Modified Example

A program running on each of the mobile station device and base stationdevice according to the present invention is a program that controls CPUand the like (a program for causing a computer to operate) in such amanner as to realize the functions according to the above-describedembodiment of the present invention. The information handled by thesedevices is temporarily held in a RAM at the time of processing, and isthen stored in various types of ROMs, HDDs, and the like, and read outby the CPU as necessary to be edited and written. Here, a semiconductormedium (ROM, a non-volatile memory card, or the like, for example), anoptical recording medium (DVD, MO, MD, CD, BD, or the like, forexample), a magnetic recording medium (magnetic tape, a flexible disk,or the like, for example), and the like can be given as examples ofrecording media for storing the programs. In addition to realizing thefunctions of the above-described embodiments by executing loadedprograms, the functions of the present invention are realized by theprograms running cooperatively with an operating system, otherapplication programs, or the like in accordance with instructionsincluded in those programs.

In a case of delivering these programs to market, the programs can bestored in a portable recording medium, or transferred to a servercomputer connected via a network such as the Internet. In this case, thestorage device serving as the server computer is also included in thepresent invention. Furthermore, some or all portions of each of themobile station device and the base station device according to theabove-described embodiment may be realized as LSI that is a typicalintegrated circuit. The functional blocks of each of the mobile stationdevice and the base station device may be individually realized as achip, or some or all of the functional blocks may be integrated into achip. The circuit integration technique is not limited to LSI, and theintegrated circuits for the functional blocks may be realized asdedicated circuits or a multi-purpose processor. Furthermore, in a casewhere with advances in semiconductor technology, a circuit integrationtechnology with which an LSI is replaced appears, it is also possible touse an integrated circuit based on the technology. Additionally,although, for the above-described embodiments, LTE and WLAN (IEEE802.11a/b/n, for example) have been described as examples of the radioaccess network, the connections may be made with WiMAX instead of WLAN.The embodiments of the invention have been described in detail thus farwith reference to the drawings, but the specific configuration is notlimited to the embodiments. Other designs and the like that do notdepart from the essential spirit of the invention also fall within thescope of the patent claims.

REFERENCE SIGNS LIST

-   1 Communication system-   5 PDN_A-   10 UE_A-   20 UTRAN_A-   22 eNB(UTRAN)_A-   24 RNC_A-   25 GERAN_A-   26 BSS_A-   30 PGW_A-   35 SGW_A-   40 MME_A-   45 eNB_A-   50 HSS_A-   55 AAA_A-   60 PCRF_A-   65 ePDG_A-   70 WLAN ANa-   72 WLAN APa-   74 TWAG_A-   75 WLAN ANb-   76 WLAN APb-   80 LTE AN_A-   90 Core network_A-   95 C-SGN_A-   100 CIOT AN_A

The invention claimed is:
 1. A User Equipment (UE) comprising:transmission and/or reception circuitry configured to perform an attachprocedure; and a controller; wherein, in the attach procedure, thetransmission and/or reception circuitry is further configured to,transmit an ATTACH REQUEST message to a Mobility Management Entity(MME), receive an ATTACH ACCEPT message from the MME, and transmit anATTACH COMPLETE message to the MME; wherein the UE indicates that, basedon transmitting the ATTACH REQUEST message, the UE requests to use of afirst processing, and the ATTACH ACCEPT message includes a networkcapability information indicating that performing for a secondprocessing is supported; and wherein the controller is configured to,interpret that performing for the second processing is accepted, basedon receiving the network capability information, and perform at leastthe second processing, after completion of the attach procedure; whereinthe first processing is a processing that the UE enters an idle modewith keeping a UE context, in a case that a message to suspend a RadioResource Control (RRC) connection is received from a base stationdevice, and the second processing is a processing that the UE transmitsand/or receives user data via the MME by using a communication path fortransmitting and/or receiving a control message.
 2. The UE according toclaim 1, wherein the UE indicates that, based on transmitting the ATTACHREQUEST message, the UE supports to perform the first processing.
 3. AMobility Management Entity (MME) comprising: transmission and/orreception circuitry configured to perform an attach procedure; and acontroller; wherein, in the attach procedure, the transmission and/orreception circuitry is further configured to; receive an ATTACH REQUESTmessage from a User Equipment (UE), transmit an ATTACH ACCEPT message tothe UE, and receive an ATTACH COMPLETE message from the UE, wherein theMME acquires that, based on receiving the ATTACH REQUEST message, the UErequests to use of a first processing, the ATTACH ACCEPT messageincludes a network capability information indicating that performing fora second processing is supported, and the network capability informationis used by the UE for interpreting that performing for the secondprocessing is accepted; and wherein the controller is configured toperform at least the second processing, after completion of the attachprocedure; the first processing is a processing that the MME enters anidle mode with keeping a bearer context, in a case that an S1Application Protocol (S1AP) message is received from a base stationdevice, and the second processing is a processing that the MME forwardsuser data between the UE and a PDN by using a communication path fortransmitting and/or receiving a control message.
 4. The MME according toclaim 3, wherein the MME acquires that, based on receiving the ATTACHREQUEST message, the UE supports to perform the first processing.
 5. Acommunication control method performed by a User Equipment (UE), thecommunication control method comprising: performing an attach procedurecomprising transmitting an ATTACH REQUEST message to a MobilityManagement Entity (MME), receiving an ATTACH ACCEPT message from theMME, and transmitting an ATTACH COMPLETE message to the MME; the methodfurther comprising indicating that, based on transmitting the ATTACHREQUEST message, the UE requests to use of a first processing; whereinthe ATTACH ACCEPT message includes a network capability informationindicating that performing for a second processing is supported, the UEinterprets that performing for the second processing is accepted, basedon receiving the first network capability information, and the UE iscapable of performing at least the second processing, after completionof the attach procedure, wherein the first processing is a processingthat the UE enters an idle mode with keeping a UE context, in a casethat a message to suspend a Radio Resource Control (RRC) connection isreceived from a base station device, and the second processing is aprocessing that the UE transmits and/or receives user data via the MMEby using a communication path for transmitting and/or receiving acontrol message.
 6. The communication control method according to claim5, wherein the UE indicates that, based on transmitting the ATTACHREQUEST message, the UE supports to perform the first processing.
 7. Acommunication control method performed by a Mobility Management Entity(MME), the communication control method comprising: performing an attachprocedure comprising receiving an ATTACH REQUEST message from a UserEquipment (UE), transmitting an ATTACH ACCEPT message to the UE, andreceiving an ATTACH COMPLETE message from the UE; and the method furthercomprising acquiring that, based on receiving the ATTACH REQUESTmessage, the UE requests to use of a first processing; wherein theATTACH ACCEPT message includes a network capability informationindicating that performing for a second processing is supported, thenetwork capability information is used by the UE for interpreting thatperforming for the second processing is accepted, the controller isconfigured to be capable of performing at least the second processing,after completion of the attach procedure, the first processing is aprocessing that the MME enters an idle mode with keeping a bearercontext, in a case that an S1 Application Protocol (S1AP) message isreceived from a base station device, and the second processing is aprocessing that the MME forwards user data between the UE and a PDN byusing a communication path for transmitting and/or receiving a controlmessage.
 8. The communication control method according to claim 7,wherein the MME acquires that, based on receiving the ATTACH REQUESTmessage, the UE supports to perform the first processing.